Beamline 9.0.2 Manual

Table of Contents

ALS Overview

Chemical Dynamics Beamline 9.0.2

Beamline Software

ALS Overview

The Advanced Light Source (ALS) is a national user facility located at Lawrence Berkeley National Laboratory in Berkeley, California. This synchrotron light source operates in top-off mode with electron energy of 1.9GeV with a continuous electron beam current around 500mA. The electrons begin their journey in a short linear accelerator before entering a booster ring where their energy is ramped up to 1.9GeV. The electrons are then injected into the storage ring where they circulate and emit the synchrotron radiation delivered to the beamlines. The ALS is optimized to produce radiation in the ultraviolet and soft x-ray regimes of the electromagnetic spectrum. Approximately forty beamlines are housed at the ALS.


Getting Started at the ALS

Before beginning work at the ALS, users need to register with the ALS User Services Office. Please read and follow the instructions for registration a few weeks before scheduled beamtime as this will allow you to begin work promptly after your arrival. If you have any questions regarding the registration process, please email ALS User Services.

For more information on the ALS, please visit their website.


Safety at the ALS

As a research facility, the ALS has many hazards, and it is important to be aware of this. The following rules have been implemented to ensure the safety of all workers and visitors at the ALS:

Open-toed shoes are not allowed on the ALS experimental floor or in the ALS labs

Food is not permitted at the beamlines. It may only be consumed in designated nooks on the outside perimeter of the ALS Floor, see Figure 1. Drinks are allowed in areas designated by a green sign on the ALS floor.

Food Alcove

Figure 1: Food may be consumed in any alcove like the one pictured above on the ALS floor. Food is no longer permitted at the BLs or on the red painted floor. This alcove is located behind BL

Always wear the proper personal protective equipment (PPE) when performing work or when entering PPE designated areas. Any of the beamline (BL) staff are willing to help select and locate the proper PPE. Closed-toe shoes, long pants, and safety glasses are required on the experimental floor.

At the BL, users may vent and work on endstations connected to terminals. The terminal is defined by the window valve directly upstream from the endstation. Never under any circumstances may a user vent and perform work on the BL components. Contact a BL scientist or the ALS control room if you have any questions regarding the BL components.

In some cases, additional training may be required before work may begin. For example, the use of a Class IV laser requires Laser Safety Training, so please plan ahead.


Experiment Safety Sheet

Since each experiment has its own unique set of hazards, the Experiment Safety Sheet (ESS) is designed to determine and mitigate all hazards. David Malone is the ALS representative responsible for the ESS paperwork and for arranging inspections where qualified safety personnel examine an experiment and its hazards before the experiment can begin

The ESS is generated when users submit a general user proposal. The user is asked to check boxes indicating the types of hazards to be used in the experiment and then fill in the details about each hazard. This information is used to populate the ESS document. Before work can begin, the hazards of the experiment must be effectively mitigated, and then ALS personnel will sign the form indicating that the experiment meets the ALS safety standards. In addition, the experimenter must have the appropriate training in order to perform work

Five hazard inspections are required for every inspection at the ALS: seismic, vacuum, electrical, mechanical, and radiation hazards. Seismic inspections are required for earthquake safety. The ALS sits near the Hayward fault line, and each endstation, as well as equipment taller than 4', must be secured to the floor. Please keep this in mind when designing an apparatus and how to align it since it will be in a fixed position

The storage ring of the ALS is maintained at a pressure of 10-10 Torr. The beamlines at the ALS are clean vacuum and no oil pumps are allowed at the ALS. Please ensure that all parts of the experiment that will be under vacuum are cleaned for Ultra High Vacuum (UHV). The lab has a UHV cleaning facility on site. Contaminated equipment must be cleaned before being attached to the BL. The vacuum inspection is required to maintain the integrity of the storage ring vacuum. Differential pumping regions may be used if a higher pressure is desired in the endstation.

All electrical components of an experiment are inspected to ensure the safety of anyone who may come into contact with the apparatus. Any non-UL certified electrical equipment must be listed on the ESS and inspected for safety concerns. Please notify David Malone in advance to ensure that the inspection may be done in a timely manner. All the equipment must be kept at the same ground potential, and the ALS will provide cables for this if needed.

The mechanical inspection is for movable parts on the endstation. The radiation inspection checks any x-ray producing machines brought to the BL as well as the possibility of exposure to the photon beam.

Depending on the nature of the experiment, other inspections may be triggered in the ESS, including inspections for lasers, hazardous or compressed gases, radioactive or biological materials. Any engineered nano material must also be entered in the ESS.

Work may begin once the ESS hazard pages have been signed, a BL scientist has authorized the experiment, and the ESS has been posted to the sector board. The BL scientist authorizes the work by signing the ESS. The ALS Environmental Health, Safety and Security (EHSS) liaison will also participate in the inspection and sign the ESS confirming that the experiment is safe. If the ESS has not been posted or does not accurately list all the hazards, this is a STOP WORK situation, and work may not begin until the situation has been rectified.

A Users Experiment Form (UEF) accompanies the ESS. This form must be filled out by the Principal Investigator (PI) of the experiment. This may be done during the inspection. The UEF gives a brief overview of the experiment and types of hazards. Each person working on the experiment must be listed on the UEF, and a signature indicates that the person is present during the experimental run. This page is posted with the ESS at the sector board and must be completed prior to starting work. The BL scientist initials the UEF for confirmation.

Changes may be made to the ESS by contacting David Malone. He will bring a functional change form to attach to the ESS, and work may then begin.


Samples and Materials

Information on how to transport the samples to the ALS may be found in the ALS user guide.

Please include all chemicals, engineered nano material, gases (hazardous and non-hazardous), radioactive samples, and biological samples on the ESS. Chemicals and gases will need to be barcoded and entered into the Chemical Management System (CMS). Please send a list of chemicals and gases to Doug Taube beforehand so he can check for shipments and enter them into the system once they arrive. Standard purity Helium, Argon, Nitrogen and Carbon Dioxide are available on-hand for purchase in Building 7 next door to the ALS. The above link also details the requirements for purchasing other types of gas not readily available, including toxic and hazardous gases.

Peroxide forming chemicals may not be stored at the ALS after an experiment concludes. They will be sent to hazardous waste, see Sample Disposal, upon completion of the run. Since storage space is limited and the cost for disposal of hazardous material is high, please order conservative quantities of chemicals and gases.

Liquid Nitrogen is also available for use. A LN2 dewar is located near the Bldg. 15 entrance, see Figure 2. When filling a portable dewar, the provided face shield and gloves must be worn. Liquid Nitrogen is also plumbed throughout the ALS and may be connected to an apparatus via 1/4 inch stainless steel pipe with Swagelok connectors. The LN2 supply for BL is shown in Figure 3. A face shield and gloves must also be worn when connecting the plumbed LN2, and the PPE is available at the BL.

LN2 Dewar

Figure 2: Portable LN2 dewars may be filled from these tanks located near the Bldg 15 entrance. The PPE, circled in red, must be worn when using the dewar.

LN2 BL plumb drop

Figure 3: Plumbed LN2 is also available for use and may be connected using the Swagelok connector, circled in red.

Use of biological or radioactive samples at the BL requires additional authorization. Please contact the Biosafety Program Manager, Bruce King, to begin the Biological Work Authorization (BWA) process. Biosafety Training may also be required.

For radioactive samples, please contact David Kestell, the health physicist, to begin the authorization process. Please include the type of material, isotopes, radioactivity, form, amount, how and where it will be prepared, where it will be stored, and how the sample will be used in the experiment. Transportation services will also need to be notified to coordinate the transfer of the material to the ALS. Additional training may be required, so please contact David or Craig well in advance.



Please send Doug Taube a list of excess or used chemicals that are no longer needed after completion of the experiment. These chemicals will be disposed as hazardous waste and removed from the CMS. All peroxide forming chemicals will be sent to hazardous waste promptly after completion of the experiment.

To dispose of biological waste, please see Doug for assistance.


ALS Facilities and Services

The following sections are taken from the ALS User Guide under the Facilities and Technical Support section.

Shipping to the ALS

All Lab personnel, including ALS staff and users, must follow the procedures detailed below for packing, labeling, and sending shipments to or from the ALS. These shipping procedures are required for all materials and equipment brought to the lab for experiments, items that are being returned for repairs or refunds to manufacturers or vendors, and any item borrowed from, or being lent to, another institution.

All items transported to or from Berkeley Lab must be received or sent through ALS or LBNL Shipping and Receiving during regular business hours - Monday-Friday, 7:00 a.m.-4:30 p.m. The items must be intended for Lab-related use only and be accompanied by proper and complete documentation.

Shipping or receiving items that have been borrowed from, or lent to, other institutions require additional Lab-specific doumentation that must be filled out before the items are handled by shipping personnel.

Packages should not be sealed as they will be inspected by Lab personnel before they are shipped. Each item or package must have the appropriate and complete documentation including a Lab Shipping Document and a valid project ID number.

Several independent carriers, including Aeronet Worldwide; Federal Express; United Parcel Service; Lynden Air Freight; and Burlington Air Express, provide a variety of shipping services to the ALS. Users can make all arrangements for shipping on-line from the carrier home pages, or fill out the necessary forms in the Receiving Area in Building 7. If you have questions about selecting an appropriate carrier, prepaying shipping costs, or require assistance with filling out shipping forms, consult Gary Giangrasso.

Shipping materials to Cuba, Iran, Libya, North Korea, Sudan, and Syria is prohibited; contact Berkeley Lab Procurement for more information.

Please contact Gary Giangrasso (510-486-4494 or ext. 4494) about any shipments that will arrive before or during your stay, and advise of any special handling instructions. This is especially important if you intend to ship hazardous materials, where storage and shipment may require advance planning. All non-hazardous shipments to the ALS should be labeled using one of the following formats:

Small Packages

ALS Group Name c/o User's name
Lawrence Berkeley National Laboratory
1 Cyclotron Road, MS 7-100
Berkeley, CA 94720

Large Packages Requiring a Forklift

ALS Group Name c/o User's name
Lawrence Berkeley National Laboratory
1 Cyclotron Road, Building 7
Berkeley, CA 94720

Please have shipments requiring a forklift arrive Monday-Friday between 8:00 a.m. and 2:30 p.m. as the ALS forklift operators leave at 3:30 p.m. Berkeley Lab technicians are available to operate forklifts after-hours for an extra charge, but it is highly recommended that ALS personnel handle the forklift if any delicate equipment is involved.

Materials should be shipped in collapsible cardboard boxes with Styrofoam and cellulose peanuts, which may be reused . Please include a packing slip inside the package with your name and the appropriate ALS address in case of lost or damaged shipments. All packages addressed to Mailstop 7-100 will be delivered to the Receiving Area of Building 7. Gary Giangrasso or Derrick Crofoot will notify users when their shipments arrive and coordinate the deliveries.

For time sensitive deliveries, please notify ALS Receiving in advance since packages are first delivered to Berkeley Lab Shipping and Receiving Department and sit there until delivery by truck to the proper laboratory building. If notified, ALS Receiving can help prevent this delay. Users who know an express package is on its way to should contact ALS Shipping Manager Gary Giangrasso with the name of the courier company and the name of the sender. Gary will ask the Berkeley Lab receiving clerks to notify him when the package arrives, and once it arrives, he will pick up the package directly from LBL receiving and see that it reaches the user by 11:00 a.m.

For equipment arriving through U.S. Customs, please contact the Berkeley Lab Receiving Office (Tel: 510-486-4935; Fax: 510-486-5668) in advance and provide the name of the carrier and the Air Bill Number of any incoming shipments. To expedite delivery of equipment from outside the U.S., please inform the Berkeley Lab customs broker of the Lab purchase order number, if available, and notification of whether or not duty must be paid.

Users shipping scientific equipment from outside the U.S. that require a temporary import bond (TIB) should contact Courtney Glover at Aeronet Worldwide (tel: 800-654-8229; fax: 650-654-8229). She can arrange both shipment and customs paperwork for equipment destined for the ALS.

Shipping Hazardous Materials

Users should consult with a Materials Specialist at their home institution regarding the proper handling and shipping of hazardous materials. Hazardous materials shipped to or from Berkeley Lab by truck must be packaged and handled according to U.S. Department of Transportation guidelines. Hazardous materials shipped by air must meet International Air Transportation Association regulations. Each shipment of hazardous materials must include pertinent Materials Safety Data Sheets (MSDSs).

Ship the smallest quantity necessary for your experiment. Use of hazardous materials on the experiment floor is limited to small quantities.

Transportation of hazardous materials in private or Berkeley Lab vehicles is prohibited. For additional information, contact Chuck Horton, Berkeley Lab Materials Specialist (ext. 5084) for information about the proper packing and safe shipment of hazardous materials or the ALS Environment, Health and Safety Program Manager (ext. 7407) for health and safety information regarding hazardous materials.

All materials should be sent to the address given in Section Shipping to the ALS.


Chemistry Lab

The Chemistry Lab may be used to prepare and store chemicals. To access the lab, users must take the required online Chemical Hygiene and Safety training. Users must also read and sign the MES-ALS safety primer form and fill out the registration placard available from Giselle Jiles at the front desk.

The Chem Lab is maintained by Doug Taube; please contact him before beginning work in the Chem Lab, and he will discuss the requirements for using the equipment, labeling work areas, storage and disposal of chemicals.


Users' Machine Shop

The Users Machine Shop has a lathe, mill, table saw, and grinders. It is located in the basement of Building 80 and is open from 7:00 a.m-4:00 p.m. Monday-Friday. After-hours access is available to trained users; check with the Control Room (Building 80, Room 140; ext. 4969) to get access.

All users must complete a 30-45 minute safety orientation before using the machines. To arrange an orientation, call Kurt Krueger (ext. 2183) during shop hours. Qualified users may use the machine shop on a walk-in basis during its regular hours. At least two people must be in the machine shop when equipment is being used during off hours; users are required to bring along a second person for safety.


Electronics Shop

In addition to supplying electronics small parts, the electronics maintenance staff is available 24 hours daily to assist users with advice, troubleshooting, and equipment repair for electronic equipment on the ALS experiment floor.


Survey and Alignment

Members of the ALS Survey and Alignment group are available to assist users in aligning their experiment and endstation equipment. In most cases, the survey crew already has the coordinates of the beamline axes so they can quickly align the experiment endstation with the photon beam. In cases where an endstation has not been marked or fiducialized with survey targets, inlet and outlet flanges can often be used to align equipment. ALS survey help is available weekdays (ext. 5469).


Hazardous Gases

Hazardous Gases are stored in room 6C across from BL 10.0.0. Flammable gases are stored in racks along the wall. Toxic and oxidizing gases are stored in locked cabinets. Please contact an ALS Floor Operator (x7464) or Doug Taube (x4806) for the key. Toxic gases may only be used in approved gas cabinets while on the ALS floor. Many of the BLs have permanent gas cabinets installed, pictured in Figure 4. The ALS also offers temporary installation of yellow gas cabinets, see Figure 5. Contact a Floor Operator for help in obtaining a yellow gas cabinet. The cabinets are connected to the ALS building exhaust and maintain a negative pressure.

Gas Cabinet

Figure 4: Permanent gas cabinet installation at BL 9.0.2. Toxic gases must be kept in these cabinets when in use or for storage.

Yellow Cabinet

Figure 5: Temporary gas cabinet installation at BL 10.0.0. Contact a Floor Operator if an extra gas cabinet is needed on a temporary basis.


Contact Information

Below is a table of common contacts at the ALS. For numbers beginning with a '4', only the last four digits of the phone number need to be dialed when calling form an on-site phone. The Accelerator Operators, Floor Operators, and Electronics Maintenance team may work on revolving shifts, so any of the people listed in those categories should be able to help. Note that all other ALS staff work only on weekdays, so please plan accordingly.

Emergencies x7911
ALS User Services and Registration Angel Hernandez (510)486-5268
ESS Support David Malone (510)486-6718
ESS Support,
Chem Lab, Waste Disposal
Doug Taube (510)486-4806
ALS Control Room
After hours contact and access
Accelerator Operators:
Matt Abreu
David Brothers
Jill Eymann
Chit Hlaing
Haris Mahic
Sean Nord
Ken Osborne
Angelic Pearson
David Richardson
ALS Floor Operators
Shutter and Light Issues
Hazardous Gas Key
Radiation and Shielding
John Pruyn
Matt Abreu
Jill Eymann
Chit Hlaing
Haris Mahic
Sean Nord
ken Osborne
x7464, (510)847-9547
x7464, (510)847-9738
ALS Receiving Derrick Crofoot
Gary Giangrasso
Todd Anderson
Vacuum, Bakeout
Water Cooling and Air Lines
Frank Zucca (510)486-4552
Water Cooling and Air Lines Jason Borsos (510)495-2403
(510)685-5851 (Mobile)
Electronics Maintenance
Electrical Safety and Equipment
Tim Kuneli
Ronny Colston
Larry Holzer
Sergio Rogoff
Ed Romero
Peter Rosado
Michael Sawada
Ron Slater (510)486-5457
Survey and Alignment Alex Gavidia (510)486-5469
ALS Users' Machine Shop Kurt Krueger (510)926-2183
Moving Equipment
Seismic Reinforement
Monroe Thomas (510)486-6423
Building Manager Jeff Troutman (510)486-7358
LabView Help Ed Domning
Brian Smith
Computer Help Cobber Lam
Tim Kellogg
EPS Help Jeremy Mentz (510)495-8197
Radioactive Samples David Kestell (510)486-7517
Biological Samples Bruce King (510)495-2768
Shipping Hazardous Materials Chuck Horton (510)486-5084
ALS EHSS Safety Liaison Jim Floyd (510)486-4499
EHSS Assistant Tennessee Gock (510)486-5013


Chemical Dynamics Beamline 9.0.2

Front End

The Chemical Dynamics Beamline uses vacuum ultraviolet (VUV) and soft x-ray light from an undulator to study chemical processes. The photon energy at 9.0.2 is tunable between 7.4eV and 30eV and is done by adjusting the gap between the magnets in the undulator. A smaller gap yields a lower photon energy. The undulator used by the BL 9.0.2 is shared with another beamline, 9.0.1; only one of these BLs may take light at any given time. A schematic for the front end of BL 9.0 is pictured in Figure 6.

Beamline Front End

Figure 6: The Front End of BL 9.0 contains the mirrors 9.0.1 M1, 9.0.2 M1, and 9.0.2 M2 and the horizontal and vertical beam defining apertures (HBDA) and (VBDA).

To direct light to branchline 9.0.1, mirror 9.0.1 M1, see Figure 6, is inserted into the beampath. 9.0.1 M1 must be out of the beam path to take light at BL 9.0.2. Be sure to verify on the EPS screen that M1 is out before taking light at 9.0.2.

M1 mirror

Figure 7: This is the external view of M1, the mirror which directs light to BL 9.0.1.

When 9.0.1 M1 is out of the beam path, light passes to 9.0.2 M1. This mirror is water cooled as it absorbs 90% of the energy from the undulator. To take light at the 9.0.2 branchline, 9.0.2 M2 must be inserted into the beam path using the BL controls software, see Section Turning a Terminal Online.

Additional hardware in the front end are the horizontal and vertical beam defining apertures, HBDA, Figure 8, and VBDA, Figure 10. They determine the gross spot size and energy distribution of the beam entering the gas filter. The HBDA is the first component encountered by the beam outside the shield wall. Since it sees such a high amount of radiation, it is water-cooled. The VBDA is located after M2.

The HBDA, see Figure 9, consists of two copper slabs placed vertically side by side. The gap or width between these slabs may be adjusted to define the horizontal profile of the beam. The VBDA also consists of two copper slabs, but these are placed one on top of the other. Adjusting the gap or width between these two slabs defines the vertical profile of the beam. The HBDA and VBDA gap is nominally adjusted between 8mm and 10mm.


Figure 8: The external view of the HBDA. The slabs, see Figure 9, may be viewed by looking through the port at the bottom right part of the picture, circled in red.

HBDA slabs

Figure 9: The internal view of the HBDA. The copper slabs may be translated and the width between them may be adjusted.

The centers of the HBDA and VBDA gaps may be translated. This translation allows for different parts of the beam profile to be seen at the terminals. Nominally, the profile at the center of the beam is preferred, and this is at position 0mm for the HBDA and VBDA. The adjustments for the HBDA and VBDA are made with the BL controls software, see Section BL Controls Software.


Figure 10: The external view of the VBDA.

A Chemical Dynamics BL schematic is pictured in Figure 11; The beam enters at the gas filter and follows a path determined by the BL optics. The upstream portion or front end of BL 9.0.2, discussed in the previous paragraphs, is upstream of the gas filter.

Beamline Schematic

Figure 11: An overview of the hardware downstream from the undulator at BL 9.0.2.


Gas Filter

The gas filter, Figure 12, behaves as a low pass filter, absorbing the higher harmonics from the undulator. Only rare gases may be used in the filter, no exceptions. The cutoff energy is the ionization energy (IE) of the gas as energies above the IE are absorbed. Argon and Helium are readily available at the ALS. If a different rare gas is required, please arrange it with us beforehand. Values for typical gases used in the filter are listed in the table below.

Gas Filter

Figure 12: The gas filter on the Chemical Dynamics BL. The valves circled in red are used to control the pressure inside the gas cell. The blue valve determines the line pressure, and the green valve opens access to the cell.

Gas Cut-off Energy (eV) Gas Cell Pressure
Argon 15.8 25-30
Helium 24.6 15-20
Krypton 14.0 25-30
Neon 21.6 25-30
Xenon 21.0 25-30

To maintain good operating condition of the vacuum pumps, the operating pressures for the gases should not exceed those listed. Filling the gas filter will be discussed in Section Filling the Gas Filter.


Terminal 3

Moving downstream from the gas filter, refer to Figure 11, light may encounter the grating in the 3 meter monochromator (mono). This grating directs the light to Terminal 3 (T3), highlighted in yellow on the left-hand side of Figure 11. The mono can hold two gratings. They are installed so that energy is dispersed vertically. One of the gratings is a low energy grating, and the other is a high energy grating, indicated by an etched in #2 on the upper left corner of the faceplate on the grating mount.

T3 Monochromator

Figure 13: The T3 monochromator may be moved by rotating the knob on top, circled in red. Once the grating is in the desired position, flip the switch, circled in red at bottom left, to the correct orientation.

The grating is moved in and out of place manually by rotating the knob pictured in Figure 13. Use the viewport to see when the grating mount is in place; it will be head-on. An electrical switch, in the lower left corner of Figure 13, must be flipped to relay the position of the grating to the BL controls software, see Section BL Controls Software. If the switch is not in the correct position, light will not reach the appropriate terminal. A small HeNe laser is available to use to align the grating. Please see the BL Scientist for help with this step.

T3 slits

Figure 14: The slit assembly at T3. The slit width is adjusted using the micrometer, circled near center of image. The slits may be viewed by looking through the circled port.

The slit assembly in Figure 14 allows for resolution adjustment at the terminal. The tag on the micrometer gives the micrometer setting corresponding to the slit width in microns. Smaller slit width yields a higher resolution. This terminal is a medium flux medium resolution terminal. For example, with the slit width adjusted to 600 microns, the resolution is approximately 22meV. The photon flux in Figure 15 was measured with the HBDA and VBDA at 8mm, a slit width of 200 microns, and Helium in the gas filter. The values on the x-axis correspond to both the undulator energy and the monochromator energy.

T3 Flux Graph

Figure 15: The flux at T3 with HBDA and VBDA at 8mm with 200 micron slit width.

The valve VVR1 in Figure 14 is a window valve; when closed, it is opaque to VUV but transparent to visible light. This allows for alignment to take place before pumping down the endstation. Window valves are located at the end of each terminal.


Terminal 1

When the grating is out, light continues down the BL to the next optic in Figure 11. M3, pictured in Figure 16, bounces the light towards Terminal 1 (T1), shown highlighted in yellow in the upper right-hand corner of Figure 11. The movement of M3 is controlled with the BL software controls discussed in Section BL Controls Software.


Figure 16: The M3 mirror tank is located after the T3 mono chamber and is directly behind the BL computer desk.

Users at T1 have the option of inserting a Magnesium Fluoride (MgF2) window, see Figure 17, into the BL. The window serves as a low-pass filter, cutting out energies above 11 eV when in the beam path. Looking at the viewport in Figure 17, we see that the MgF2 window is in the beam path.

Magnesium Fluoride Window

Figure 17: The MgF2 window for T1 is located between M3 and M7. The knob circled in red allows users to move the window in place.

T1, see Figure 18, does not have a slit assembly and is a high flux, low resolution terminal. The resolution is controlled by adjusting the width of the HBDA and VBDA. The flux graph in Figure 19 was taken in August of 2005. The MgF2 window was out of the beam path and Argon was in the gas filter. The measurements were taken with VBDA and HBDA widths at 8 mm.


Figure 18: The window valve and interlocking IG for T1. In this picture, T1 is connected to the aerosol endstation shown on the far right.

T1 Flux Graph

Figure 19: Photon Flux vs. Undulator Energy for T1.

The M7 mirror, see Figure 20, may be inserted into the beam path to redirect the light to the 3 meter mono for Terminal 4 (T4), highlighted in yellow in the upper right-hand corner of Figure 11. The movement of M7 and this monochromator are controlled with the BL controls software, see Section BL Controls Software.


Figure 20: The M7 mirror tank is located right before T1 and directs the light to T4.

T4 contains one grating and its movement is controlled entirely on the computer, see Section BL Controls Software. A slit assembly after the window valve, see Figure 21, is used to control the resolution. The resolution at T4 is comparable to the resolution at T3.

This terminal was designed to be a medium flux medium resolution terminal similar to T3. The flux at T4, see Figure 22, is not as high as T3, and we are investigating the source of the loss. The measurements were taken with the grating set at zero order so the monochromator behaves as a mirror. The HBDA width and VBDA width are set to 8mm.


Figure 21: The slit assembly at T4. The slits may be adjusted with the micrometer circled in red.

T4 Flux Graph

Figure 22: This graph shows the flux at T4 with the grating in zero order. The HBDA and VBDA are set to 8mm.


Terminal 2

If M3 is out of the beam path, refer to Figure 11, light travels to M4X, see Figure 24, where it is directed to Terminal 2 (T2). The endstation at T2, shown in Figure 23, is a permanent Time of Flight (TOF) machine, which utilizes Secondary Ion Mass Spectrometry (SIMS) to produce images.

Imaging Machine

Figure 23: The imaging machine at T2.

T2 also utilizes a MgF2 window, located directly after M4X, see Figure 24. The MgF2 window may be inserted into the beam path by rotating the knobs shown in Figure 24. The viewports allow the user to see when the MgF2 window is in place.


Figure 24:The mirror M4X directs light to T2. Downstream is the Magnesium Flouride window, which may be moved in and out of the beam path by rotating the knob circled in red.

This terminal is designed for high flux, low resolution similar to T1. The flux graph is pictured in Figure 25. The measurements were taken with HBDA and VBDA set at 8mm with Argon in the gas filter. The MgF2 window was out of the beam path.

T2 Flux Graph

Figure 25: The flux measured at T2 with HBDA and VBDA set to 8mm and argon in the gas filter.

A complete list of the optics, as well as their specifications, that are used at BL 9.0.2 may be found on the chemical dynamics website.

Always wear the appropriate PPE when doing work on the BL. Safety glasses should be worn at all times when performing work at the BL; they are not required when working at a desk. Safety glasses may be found near each terminal, stored in the top lid of the tool boxes. Please ask for assistance if you cannot find a pair.

Nitrile gloves are also located at each terminal. Cryo gloves are located near T3 and must be used when handling LN2. If other gloves are required, please give advance notice so we may determine if they are available.

The BL has a chemical spill kit stored near T3, see Figure 26. Please read and follow the Spill Response Procedures before using the spill kit.

Spill Kit

Figure 26: The chemical spill kit is located beneath the EPS computer at T3.

Please secure all equipment and gas cylinders with the proper restraints. Gas cylinders must be restrained with chain or hose clamps at two points. Improperly secured equipment may pose a hazard during an earthquake.

All walkways and exit paths must be kept clear at all times. Walkways must be a minimum of 3' wide to meet safety requirements for evacuation. Please keep the BL space tidy. Put unused equipment and tools in the proper storage place. Good housekeeping saves time and removes hazards. Since the BL is shared by as many as three user groups at a time, good housekeeping allows each to find the proper equipment or tools when needed.

Non-toxic cleaning solvents may be used in small amounts at the BL. All other work must be done in the Chemistry Laboratory, see Section Chemistry Lab.

Food is not permitted on the experimental floor. Please use the nooks on the outside perimeter of the ALS to store and eat food.


Beamline Software

Light at beamline 9.0.2 is controlled by two systems: the Equipment Protection System (EPS) and the LabView BL Controls software on the Beamline Computer. The latter system will be discussed in Section BL Controls Software.

Equipment Protection System

EPS screen

Figure 27: This is the main interface screen for the EPS on BL 9.0.2. This screen allows the user to control various valves along the BL.

The EPS is designed to protect the storage ring as well as components of the beamline in the case of vacuum failure. The Controls Troubleshooting website offers definitions of basic EPS components.

The graphical user interface of the EPS is pictured in Figure 27. Notice the eight tabs across the top of the screen. The tab labeled IG Readings gives pressure readings in Torr for the interlocking ion gauges (IG). A valve is interlocked to the IG reading of the chamber directly downstream. For example, 9.0.2 VVR1, before the gas filter in Figure 27, is interlocked to 9.0.2 IG1. If the pressure reading at 9.0.2 IG1 is too high, then valve 9.0.2 VVR1 cannot be opened or will close.

The values shown on the IG Readings tab, Figure 28, may vary slightly from the values given on the IG controllers. As long as the variation is within the same half decade/order of magnitude, the valves may be opened safely. If the discrepancy is large, do not open the valves without consulting BL staff.

Ion Gauge Readings

Figure 28: Readings of the main ion gauges on the beamline.

In order to access light at an endstation, the user needs to know how to operate the valves in Figure 27. The gray region in the upper left corner of Figure 27 is located behind the shield wall, and the valves in this region may only be controlled by a Floor Operator (FO). The FO inserts a key at the Beamline Chassis allowing him/her to manipulate the valves. The valve labeled PS1 is the photon shutter, and it controls access of synchrotron light to the BL. When PS1 is closed, light is restricted from the beamline, and a floor operator will need to be contacted to open the shutter.

Just outside the gray region is a valve labeled PSS1, the Personal Safety Shutter. The PSS is in place to protect workers on the BL in the instance that harmful radiation may be emitted through the storage ring shielding. Although this valve is behind the shield wall, as depicted by the thick gray line to the right of the valve in Figure 27, BL users may control this valve. PSS1 is interlocked to PS1, so it may only be opened if PS1 also opens. This valve is used to restrict or access synchrotron light at the terminals.

If a NOT symbol is shown to the right of a valve, then that valve may not be opened, see PSS1 in Figure 27. Right click on the symbol to see why the valve may not by opened. For example, the following details are displayed for the NOT symbol next to PSS1:

9.0.2 VVR1 is not open.
9.0.2 VVR2 is not open.

These valves, when closed, cannot take the power from the synchrotron beam, and the EPS requires them to be open before the safety shutter may be opened. Once the two valves are opened, the NOT symbol next to PSS1 will disappear, and PSS1 may be safely opened.

Valves may be opened by right clicking on the valve and selecting open. The valve should turn yellow and then green. A green valve indicates open. A red valve indicates closed. If a valve remains yellow, then something is amiss with the valve. Usually this is due to an unplugged electrical connection or air line at the valve. If these appear to be plugged in, then contact BL staff for help or contact the ALS Control Room at extension 4969 after hours.

The same color scheme applies to the ion gauges. A green ion gauge indicates that the pressure in the region is good. A red ion gauge indicates that the pressure is too high or the gauge may be off. Remember that the upstream valves may only be opened if they are followed by a green ion gauge. If the ion gauge is flashing yellow, click the -Reset- button in the upper right corner of the EPS screen, see Figure 27.

The 9.0.1 tab controls the valves on BL 9.0.1, and we should never have to use this screen. The 9.0.2 T* tabs allow users to control the final valves at each terminal. A sample of this screen is pictured in Figure 29.

T1 EPS Screen

Figure 29: Screenshot of one of the endstation control interfaces. These screens control each one of the four endstations individually.

Notice at the bottom of Figure 29 that the Mono is in T3. This indicates that light may only be taken at T3 as it will bounce off the grating after it leaves the gas filter.


Beamline Controls Software

The LabView Beamline Controls allow the user to adjust settings for Beamline hardware relating to the photon beam, including manipulation of the photon energy distribution, the beam position, and spot size. The front panel is pictured in Figure 30.

BL Controls Interface

Figure 30: The LabView BL 9.0.2 Control Panel is used to adjust settings for the photon beam.

In the middle of the screen, the current readings for the BL and the storage ring parameters are displayed. Display on the right-hand side are buttons that allow a user to direct the photon beam to different terminals. The process of turning a terminal online will be discussed in Section Turning a Terminal Online.

The left-hand side of the screen in Figure 30 displays a box with tabs across the top. The first two tabs, HBDA and VBDA, show the motor positions for the Horizontal Beam Defining Aperture (HBDA) and the Vertical Beam Defining Aperture (VBDA).

The mirrors tab displays the motor positions for all the mirrors in Figure 11. Notice that M4x has two degrees of freedom. Similar to the EPS system, the BL controls software displays the ion gauge readings for the BL under the ION Gauges tab.

The motor values shown on all these tabs are read-only. They may be adjusted using the Motor

The final two tabs T3 Energy and T4 Energy, see for example Figure 31, display read only values for the angle and energy. If the undulator energy and Mono Energy display the same value, then Compensation is selected, see button in bottom left corner of Figure 30. Compensation means that the monochromator moves as the undulator gap moves, so that the energy seen at the terminal is the same as the energy from the undulator. If compensation is turned off, they move independent of each other.

T3 Energy Tab

Figure 31: The T3 Energy tab on the BL controls front panel. This box contains both read-only and manipulation buttons.

From the T3 Energy and T4 Energy tabs, users may change to zero-order position by selecting Go to Zero Order. In this position, the grating behaves as a mirror. Additional buttons for the T3 mono allow the user to select the grating and adjust the offset. The offset adjustments are typically on the order of 0.001mm. This offset adjustment is here because the mechanism for moving the grating in and out does not produce a repeatable in-position.

These zero order adjustments are the only motor manipulations that may be performed from this screen. All other adjustments must be made from the Motor Display screen, see Figure 32, accessed by selecting Motors from the menu bar and then Display.

Motor Display

Figure 32: This screen allows the user to adjust values for various motors.

Click -Move- to move the selected motor. The following motor values may be adjusted from this screen: M2, M3, M4 Yaw, M4 Roll, M7, T3 Grating Angle, T4 Grating Angle, Undulator Energy, Mono T3 Energy, Mono T4 Energy, HBDA Position, VBDA Position, HBDA Width, VBDA Width, and the Undulator Gap.

Note that the Grating Angles and Mono Energies are coupled as are the Undulator Gap and Undulator Energy.

The Motor Display screen may be operated in two modes: absolute mode, shown in Figure 32, and jog mode. Change modes by pushing the button under -Mode-. In absolute mode, the motor will move to the value entered in the text box to the left. In jog mode, the motor will move that value above or below its current value. This mode is useful for fine adjustment while absolute mode is useful for gross adjustment and known values.

If you would like to monitor a signal while varying a parameter of the beam, you may use the scanning menu of the program. The Time Scan selection under Scanning monitors a signal over time. The Single Motor scan allows a user to vary one motor over a set of parameters, see Figure 33. The parameters are declared in the Setup Single Motor Scan Parameters window in Figure 33. Any of the motors listed above may be varied. The Two motor Scan is similar, but an additional motor's values may be varied.

Single Motor Scanning Screen

Figure 33: The Single Motor Scan monitoring screen and the parameters setup.

TCP Screen

Figure 34: This screen allows a user to add their IP Address of computers able to communicate with the BL Controls computer.

Some users have developed their own LabView interface to communicate with the BL controls. For the computers to talk to each other, you must set up a TCP/IP connection. This is done by selecting Beamline from the menu bar and then Setup TCP Server. A window, shown in Figure 34, will pop up where the TCP addresses are stored.

If the desired IP Address is not found in the list under Client Names, enter it when Client Names reads: localhost. Also verify that the LocalPort of the BL computer matches the LocalPort used in the outside LabView programs.


The Polynomial

The undulator gap, Ug, determines the energy distribution for the BL. The energy read off by the computer is calibrated to the undulator gap with a third order polynomial, E = a0 + a1Ug + a2Ug2 + a3Ug3. The coefficients in the polynomial may be changed by selecting Motors and then Setup Parameters.

When filling the gas filter, ensure that the PSS1 and 9.0.2 VVR1 are closed. The next step is to pump out the lines and the gas cell. Make sure the valves on all the gas cylinders are closed. Open the valve labeled VVR1B or the Gas Inlet on the EPS screen, see Figure 27. At the gas filter, open the green valve, see Figure 12, to the gas cell. The gas cell and lines should now be pumping down. The pressure may be monitored to the right-hand side of the gas filter on the gauge labeled Gas Cell, shown in Figure 35.

Gas Cell Pressure Gauge

Figure 35: This rack gives the relevant pressure readings for all the differential pumping regions and the gas cell in the filter. The reading circled in red is for the gas cell and is given in Torr.

When pumping down the cell, the pressure should drop below 1 Torr. At this point, manually close the green valve to the gas cell. Open the manual valve on the gas cylinder and adjust the regulator to about 35 psi. At the filter, slowly open the green valve while monitoring the pressure of the gas cell. If the pressure is too high, the interlocked Gas Inlet valve on the EPS will close, and the process must start over. The blue valve in Figure 12 may be adjusted while opening the green valve in order to achieve the desired pressure in the gas cell.


Turning a Terminal on-line

To take light at a terminal, first begin at the EPS screen. Verify that the PSS1 is closed. Next, verify that the mirrors are in the appropriate position for 9.0.2; look at the left-hand side of the EPS screen, Figure 27, near the gray box labeled 9.0.2. BL 9.0.2 may take light when the indicators read 9.0.1 M1 Out and 9.0.2 M2 In.

Select 9.0.2 EPS online on the EPS screen, see the right-hand side of the screen in Figure 27. M1 and M2 are moved into the correct positionse from the BL controls screen by selecting Set to T[1,2,3,4] on the right-hand side, see Figure 30. If switching between terminals on BL 9.0.2, first close the PSS1 and then take the online terminal offline on the EPS before proceeding. To use T1, T2, and T4, verify that the T3 mono is out of the beam path, and the switch is set to Out, see Section Terminal 3.


Terminal 1

At the BL Controls screen, Figure 30, select Set to T1. This will move M2 and M3 into position and M7 out of the beam path. On the EPS screen, Figure 27, select T1 EPS Online, and open the following valves: 9.0 VVR3, 9.0 VVR4, 9.0.2 VVR1, 9.0.2 VVR2, 9.0.2 VVR3, and 9.0.2 VVR4. The final valve VVR1 may remain closed during alignment as it is transparent to visible light. When ready to take measurements, be sure to open this valve as it will not pass VUV or X-rays. The PSS1 may now be opened, and white light should appear at the terminal.

M3 may be jogged slightly to help align the beam.


Terminal 2

At the BL Controls screen, Figure 30, select Set to T2. This will move M2 into position and M3 out of the beam path. Light may then pass to M4X where it is bounced to T2. On the EPS screen, Figure 27, select T2 EPS Online, and open the following valves: 9.0 VVR3, 9.0 VVR4, 9.0.2 VVR1, 9.0.2 VVR2, 9.0.2 VVR3, and VVR1, VVR2. The final valve VVR5 may remain closed during alignment as it is transparent to visible light. When ready to take measurements, be sure to open this valve as it will not pass VUV or X-rays. The PSS1 may now be opened, and white light should appear at the terminal.

M4X may be jogged slightly to help align the beam.


Terminal 3

Move the T3 mono into place and flip the switch to In, see Section Terminal 3. At the BL Controls screen, Figure 30, select Set to T3. This will move M2 into position. On the EPS screen, Figure 27, select T3 EPS Online, and open the following valves: 9.0 VVR3, 9.0 VVR4, 9.0.2 VVR1, and 9.0.2 VVR2. The final valve VVR1 may remain closed during alignment as it is transparent to visible light. When ready to take measurements, be sure to open this valve as it will not pass VUV or X-rays. The PSS1 may now be opened, and white light should appear at the terminal.

The grating may be tweaked by slight manual jogging of the knob pictured in Figure 13. Use the HeNe laser to align the beam from left-right. Once the beam is centered on the target, use the BL controls software to move the beam up and down by adjusting the zero order offset. The zero order offset adjustment is typically on the order of 0.001mm from the saved value.


Terminal 4

At the BL Controls screen, Figure 30, select Set to T4. This will move M2, M3 and M7 into position. On the EPS screen, Figure 27, select T4 EPS Online, and open the following valves: 9.0 VVR3, 9.0 VVR4, 9.0.2 VVR1, 9.0.2 VVR2, 9.0.2 VVR3, 9.0.2 VVR4, and VVR1. The final valve VVR2 may remain closed during alignment as it is transparent to visible light. When ready to take measurements, be sure to open this valve as it will not pass VUV or X-rays. The PSS1 may now be opened, and white light should appear at the terminal.

M3, M7 and the mono T4 grating angle may be jogged slightly to help align the beam.