EXPERIMENTAL STATION 4-2

CURRENT STATUS: Open
SUPPORTED TECHNIQUES: Biological Small Angle X-ray Scattering/Diffraction
Macromolecular solution x-ray scattering
Lipid membrane diffraction
Fiber diffraction
Time-resolved x-ray scattering/diffraction
Small-angle single crystal diffraction
Ultra small-angle x-ray scattering (under development)
MAIN SCIENTIFIC DISCIPLINES: Biology
% TIME GENERAL USE: 100%
SCHEDULING: Proposal Submittal and Scheduling Procedures
Current SPEAR and Beam Line Schedules
SOURCE: 20-pole, 2.0-Tesla Wiggler ID End Station
BEAM LINE SPECIFICATIONS:
  energy range grating type resolution
DE/E
spot size flux angular
acceptance
focused (crystal)
    6000-18000 eV

  ~5 x 10-4
     ~0.2 x 1.0mm
 
< 1.0 mrad
focused (multilayers)
    8000-12000 eV

  ~3 x 10-2
     ~0.2 x 1.0mm
 
< 1.0 mrad
OPTICS: Bent cylinder mirror, silicon, Rh-coated
Radii: 15.4m vertical (adjustable) x 57mm horizontal
Mean angle of incidence: 3.8mrad
Cut off energy: 17.5keV
Magnification: 1.0
MONOCHROMATOR: Parallel crystal geometry
Si(111), Mo/B4C multilayers
Upward reflecting
Liquid nitrogen-cooled monochromator (same as other insertion device hard x-ray stations)

Monochromator Crystal Glitch Library

Crystal changes need to be scheduled and coordinated in advance with BL support staff.
ANGULAR RANGE:
Distance(m)   Typical Q (2ps) Range(Ã…-1)
0.25   0.045 - 3.6
0.45 0.024 - 2.2
0.65 0.017 - 1.6
1.10 0.010 - 1.0
1.65 0.0068 - 0.67
2.40 0.0045 - 0.46
3.40 0.0034 - 0.33
E=11keV, 4mm circular beam stop assumed
INSTRUMENTATION: Please refer to http://ssrl.slac.stanford.edu/~saxs
DATA ACQUISITION AND ANALYSIS: Data acquisition: Blu-ice, HiPic
see: http://www-ssrl.slac.stanford.edu/~saxs/daq/daq.htm

Data analysis: SasTool, fit2D
see: http://www-ssrl.slac.stanford.edu/~saxs/daq/daq.htm

X-ray Data Booklet
RESPONSIBLE STAFF: Thomas Weiss, 650-926-5455
Tsutomu Matsui, 650-926-5598 (office)
Ping Liu, 650-926-4036 (office)
BEAM LINE PHONE NUMBER: 650-926-5242
On-site Users: Contact the Duty Operator at 9-926-4040
GENERAL DESCRIPTION: BL4-2 is a small-angle scattering station dedicated to structural biology studies primarily on non-crystalline systems. The 20-pole wiggler in combination with the multilayer monochromator provides high brilliance x-ray beam for time-resolved studies down to milliseconds. This facility covers the range of characteristic length scale of a few Angstroms to a few micrometers by the combined use of a pin-hole geometry camera, which can be automatically configured to have one of 7 sample-to-detector distances, and a separate ultra small angle scattering setup. A Rayonix MX225-HE detector is our primary detector. A Dectris Pilatus 300K pixel array detector system is used for fast time-resolved studies. The facility provides a large selection of sample handling devices, such as stopped-flow rapid mixers, capillary flow cells and automated sample changer for solution scattering.
Sample Preparation Labs: The SSRL Structural Molecular Biology (SMB) Sample Preparation Laboratories are available to users by prearrangement. To use a laboratory, users must complete laboratory training, and provide a list of all chemicals to be brought, used or stored in the Sample Preparation Laboratory. For details, contact Cynthia Patty (650-926-3925).
SCIENTIFIC APPLICATIONS /
SELECTED RESULTS:
ENGINEERING NOTES: http://www-ssrl.slac.stanford.edu/safety/ beamlines/bl4/

SSRL | Beamlines | User Admin | Safety

Last Updated: 28 JAN 2011
Content Owner: Thomas Weiss
Page Editor: Nikola Stojanovic