University of Wisconsin-Madison

The deadline for beamtime requests is approaching rapidly. Submittal forms
are available in several ways:

A) As Word file on the SRC web page at http://www.src.wisc.edu/currentusers/online_forms/
1999_2000_beamtime/
B) As hardcopy from Pamela Layton)
C) As text file via e-mail from Pam Layton

Submittals should be mailed to:

Beamtime Request
Synchrotron Radiation Center
University of Wisconsin-Madison
3731 Schneider Drive
Stoughton, WI 53589

There are new options for beamtime requests available that allow faster Access and longer duration. Beamtime requests can now be submitted twice a year (February and August), and the duration of proposals can be 6, 12, and 18 months. Users who prefer the current system will be able to continue with the previous 1-year cycle with a proposal in February. Scheduling will be done every 6 months.

NEW UNDULATOR BEAMLINE OPERATIONAL

The new U1 undulator beam line has become operational. It combines an electromagnetic undulator with a 4m normal incidence monochromator for high resolution valence electron studies, such as in high temperature superconductors and atoms/molecules. This beam line will carry the work done on the trusted 4m-NIM bending magnet line into the generation of undulator light sources, providing an order of magnitude higher flux-resolution product. Tests of the beam line have been conducted by Mark Bissen and Mary Severson using an ionization chamber. Autoionizing resonance lines of neon at 21.5 eV give a FWHM of 0.47 meV, those of argon at 14.76 eV a FWHM of 0.35 meV, which is close to the theoretical limits at the slit settings used. This project is based on a NSF grant obtained by Juan-Carlos Campuzano (U. Illinois Chicago), together with Tai Chiang (U. Illinois Urbana), Rong Liu (Michigan State), and the SRC. The beam line was designed, constructed, and tested by SRC staff under the lead of Greg Rogers.

SRC CRYOSTAT TESTED WITH SCIENTA ANALYZER

A closed-cycle He cryostat has been acquired by SRC for low temperature experiments in conjunction with the high-resolution Scienta analyzer. It consist of a Sumitomo cold stage with a cooling power of 1 W at 4.2 K and a holder that allows bringing in samples from a load lock. The samples are mounted on 3/4-10 NC Ti-slugs, which are screwed into the cold stage. A built-in heater which allows temperatures up to 360K with a temperature stability of a few mK. Different directions in k-space can be mapped by combining a rotation of the whole cryostat (for scanning the polar angle) and an azimuthal rotation of the sample holder (around the sample normal). For details on using the cryostat contact Hartmut Hoechst at: hhochst@facstaff.wisc.edu

NEW STAFF SCIENTIST

Ralf Wehlitz will join the SRC in May as Assistant Scientist. His background is in atomic spectroscopy with synchrotron radiation. Some of his recent work on triply-ionized lithium (Phys. Rev. Lett. 81, 1813 (1998)) was highlighted in Physics Today, Nov. 1998, p.9. Welcome to Madison!

DATE FOR THE 1999 SRC USERS MEETING IS OCT. 8, 9

Friday/Saturday Oct. 8, 9 has been set as date for the 1999 SRC Users Meeting after coordinating with as many other light sources and meetings as possible. Please let Franz Himpsel ( himpsel@comb.physics.wisc.edu ) know if there is a potential conflict remaining.