BNL 34710 INFORMAL REPORT BNL--34710 DE85 000290
Synchrotron light Source BROOKHAVEN NATIONAL LABORATORY DISTRIBUTION OF THIS DOCUMENT IS UNLIMITED ..M The National Synchrotron Light Source the storage ring vacuum chamber to mirror The NSLS is a national user facility avail- (NSLS) is designed to provide the world's assemblies or apertures where it is further able without charge to users. Proprietary brightest continuous sources of X-ray and channeled down two or three separate work can be done on a full cost recovery UV radiation. It is also the first X-ray facil'ity experimental beam lines. With a total of 44 basis, with the option to retain titleto inven- in the United States dedicated for use as a ports on the two storage rings, this leads to tions resulting from research at the NSLS. synchrotron light source. There is a 750 the possibility of having as many as 90 There are several modes of use of exper- MeV electron storage ring with 16 ports for experiments (1 for each beam line) operat- imental facilities. A large number of beam VUV and IR research and a 2.5 GeV elec- ing simultaneously at the NSLS. lines have been designed and constructed tron storage ring with 28 ports for X-ray Electrons moving along an arc at veloci- by the 30 Participating Research Teams research. ties much less than the speed of light emit (PRTs). PRTs are, for the most part, user Bursts of electrons are first generated by radiation in a dipole pattern. However, at groups from outside BNL with large, long- an electron cjun, accelerated to 70 MeV by a velocities approaching the speed of light, range programs which have been approved linear accelerator (LINAC), and further this radiation is thrown forward in a narrow by the NSLS Program Advisory Commit- accelerated to 750 MeV in the booster syn- cone in the electron's direction of motion tee. The PRTs are given priority for up to chrotron which also groups the electrons much like a laser beam. This concentration 75% of their beam line's operational time. in 5 bunches equally spaced around its 28 of radiation in the forward direction is General users, who may have a less sub- meter circumference. The booster then responsible for the high intrinsic bright- stantial need for the use of the facility, are injects the 750 MeV electron bunches into ness. The radiation is also completely polar- scheduled for both PRT beam lines and for the VUV storage ring or into the X-ray stor- ized, with the electric ve:tor lying in the lines built by NSLS for the general commu- age ring where they are accelerated to their plane of the electron's orbit. The spectrum nity. final 2.5 GeV energy. The booster and stor- of synchrotron radiation extends from the age rings use a common r.f. accelerating infrared up to gamma rays. Since the elec- frequency of 50 MHz. An ultra-high vacuum trons are accelerated in bunches, the result- environment is maintained in each storage ing synchrotron radiation also comes in ring to allow the electrons to circulate for pulses too (less than 10~9 sec in duration). hours at velocities close to the speed of These unique properties ot synchrotron light before being knocked out of their radiation (high brightness, broad and con- orbit by residual gas atoms. tinuous energy range, high polarization Synchrotion radiation is produced when and time structure) have attracted scient- these relativistic electrons are bent in arcs ists from universities, government labora- by the storage ring dipole magnets. The tories and industry. radiation is emitted at a tangent to each point of the arc and travels through ports in
DISTRIBUTION OF THIS DOCUMENT IS EXPERIMENTAL BEAM PORTS (16) VUV EXPERIMENTAL STORAGE BEAM PORTS (28) RING
RADIATION PATTERN
MECHANICAL EQUIPMENT X-RAY STORAGE RING
rj j '• X-RAY SHIELD TUNNEL NATIONAL SYNCHROTRON LIGHT SOURCE BROOKHAVEN NATIONAL LABORATORY ENERGY (eV) 1000 100 10 -1- ~r | i i I i i I ' ' 10" -
< - /^^ 1j\. -
1016 able (2000-40r)0A) UV source of average
0.3 0.6 i I I I 0.1 1 10 100 WAVELENGTH (A) When PRT proposals were first solicited in 1979, there was an overwhelming re- sponse from the scientific community which clearly perceived the advantage of having dedicated experimental facilities on high brightness sources of X-ray and UV radiation. The PRT policy has made it pos- sible to simultaneously build up scientific capability in a number of different areas. The facility has a wide range of research equipment available to users for basic and applied studies in condensed matter, sur- face science, photochemistry and photo- physics, lithography, crystallography, small- angle scattering, metallurgy, x-ray micro- scopy, etc. (See Table I) The involvement of scientists from the full spectrum of U.S. institutions is seen in the lists of PRT X-ray and UV beam lines. (Tables Hand III) DISCLAIMER
This report was prepared as an account of work sponsored by an agency of the United States Government. Neither the United States Government nor any agency thereof, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsi- bility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. Refer- ence herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise does not necessarily constitute or imply its endorsement, recom- mendation, or favoring by the United States Government or any agency thereof. The views and opinions of authors expressed herein do not necessarily state or reflect those of tl.'- United States Government or any agency thereof.
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"a 3 ' X3 O 2L O o > •< < 3" a m CD XI < > CD O X c ™n = nra p Si. i. »• 3Ho g " "^. ~CQ 2 3" 33 3 O CD o ;* ~. o x 5 01 CO CD CD S T3 if 3 cl 3" 3 01 cB" o -* o < 2. ics *o< Q_ a n 3 eo o' >< < CD •§. m 3 =T tall o aqn < ra y o ^ -ra y Ulpe c OSC i ••< CO 3 x rn c > m X m CQ o > >< •< 3 T3 2- hotoel e f d Stat e I/ O arimen t c Circu l Tl y Scatt c aphy/ D Microp r atterin c 5s o o hotoel e CD XI malou s CD co Adoos i en" _^ Q (A 01 >cat i Iro n srsi v Pro - rn - n be , n c" en D CD UOJ : J'f CD CD o cD 2ISL S o 3—*\ 3 O 5' ffr a tte r 01 is m g CQ ction , in g MIC A L E 1 Wi n Wi n Si x Hig l Fas t wit h Sp e life t Int e 2-L ) Si x Ext e Hig l Hig l Fre ; Hig i cn CO Hel i 3 | O X n energ y polar i ;imu m coun t re XB W im e studie s (ti r t photo n coun i quadrjpol e r circl e diffract o ivo studie s 15 0 jnde d rang e g r sne l zon e plat h intensit y an d h temperature / dowe d sampl e dowles s supe r circl e spectro n ctromete r (2(X CQ nsit y variatio n L DAT A iograph y ur n an d UH V c (300 A "A (10eV Cam , D as s I cel l 3 o A CD o hi g CD UJ s° 3 Ol 3 3 O CD o CD CD CD < -1MHz ) (1MHz ) fo r flu o noppe r monocl " nochromato r h resolutio n to r i pressur e cen s gratin g monoc l ) esolutio n <20 0 . 5 Tesl a electr o o nts/Feature s s fo r gase an d ) , Fas t 1- D an d 0 a l monochrom f c nozzl e bea m (0 o >ispectromete r ° A (500eV CD en -* c CO cn TABLE II NSLS UV BEAM LINES A(A) U 1. EXXON SEXAFS, ARUPS, XPS 10-1200 ERG Infra-red vibr'tnl. spect. 104-106 NIM U 2. NSLS Diagnostics U 3. LANL/SANDIA/U.CALIF/ Spectroscof y 10-1200 ERG LAWRENCE LIVERMORE Radiometry 6-100 U 4. BELL LABS A) SEXAFS/ARUPS/XPS 12-1200 PGM B) ARUPS 80-5000 TGM C) ARUPS/ABS/REFL 400-6000 NIM U 5. NSLS Free Electron Laser U 6. IBM Lithoqraphy White U 7 BNL/SUNY A) ARUPS/XPS/SEXAFS 15-1200 PGM B) Gas solids TGM U 8. IBM A) ARUPS 18-2000 TGM B) ARUPS 80-2500 TGM C) EXAFS/SEXAFS 8-100 Fresnel D) Microscopy Zone Plate U 9. NSLS/BNL-CHEM. A) Fluorescence lifetime 1050-12,000 NIM NSLS/BNL-BIO. B) Dichroism/fluorescence 1200-300,000 NIM U10. TENN/NBS/ORNL X-ray fluorescence 12-120 SXES U11. NSLS/BNL-CHEM. Gas phase spectroscopy 300-2000 NIM U12. PENN/ORNL/XEROX A) ARUPS 15-1200 TGM B) ARUPS 80-2500 TGM C) Infra-red vibr'tnl. spect. 104-106 NIM U13. U14. NSLS A) ARUPS/XPS/SEXAFS 15-1200 PGM NSLS B) Optics R&D 8-100 DCM U15. NSLS/SUNY TGM monochromator/microscope 12-50 TGVI U16. Techniques: ARUPS = angle-resolved ultraviolet photoemission spectroscopy, XPS = X-ray photoemission spectroscopy, EXAFS = extended X-ray absorption fine structure, SEXAFS = surface EXAFS. Monchromators: ERG = extended range grasshopper, PGM — plane grating monochromator, TGM = toroidal grating monochromator, NIM = normal incidence monochromator, DCM = double crystal monochromator. SXES = soft X-ray emission spectrometer. (Resolving powers of above monochromators are in the range of 100 -1000.) TABLE III NSLS X-RAY BEAM LINES X 5. BNL PHYSICS Compton Backscattering — Nuclear Physics X 9. JOHNSON RESEARCH FOUNDATION A) EXAFS (Biology) B) Scattering X10. EXXON A) Scattering B)EXAFS C) Crystallography X11. N.C. STATE/CONN./BNL/G.E./U.WASH./ EXAFS MOBIL/DuPONT/ARGONNE X12. NSLS/BNL-BIO. A) Small Angle Scattering B) Protein Crystallography X13. NSLS/BNL-CHEM. Crystallography/Diffuse Scattering NSLS/BNL PHYSICS/PENN/SUNY/ Energy Dispersive Diffraction ALLIED CHEM/DuPONT EXXON beam lines on Port X10ot the X-ray storage X14. ORNL A) Diffuse Scattering ring. These three beam lines are among approxi- B) Microprobe mately 26 X-ray beam lines commissioned in 1984 C) Topography and 1985. X15. BELL LABS A) Scattering X16. BELL LABS B) Interferometry C) EXAFS/Scattering D) Spectroscopy X17. (Reserved for Wiggler) X18. PURDUE/MIDWEST Diffraction W.VA/PITT./GULF/ASHLAND/UOP EXAFS X19. NSLS EXAFS/SEXAFS/XPS NSLS/SUNY Topography X20. IBM/MIT A) Scattering [Low Q Resolution] B) Scattering [High Q Resolution] X21. SUNY Scattering X22. BNL PHYSICS A) Scattering [High Q Resolution] B) Scattering [High E Resolution] X23. NRL/NBS A) Topography X24. NRL/NBS B) Small Angle Scattering C) EXAFS/SEXAFS D) Crystallography E) XPS/UPS X25. WiqglerTest X26. U. CHICAGO/BNL Microprobe BNL PHYSICS/CORNELL/TEXAS A&M/ Atomic Physics U. TENN. XAFS = extended X-ray absorption fine structure, SEXAFS — surface EXAFS, UPS = ultraviolet photoemission pectroscopy, XPS = X-ray photoemission spectroscopy Experimental operations began on the 1 /Jim UV ring in August, 1982. There are now a large number of beam lines producing new results in diverse scientific areas. A few of these results are highlighted below. 1 urn X-ray Lithography (Port U6) The high intensity and collimation of synchrotron radiation from the VUV stor- age ring has been utilized on the IBM lithog- raphy line (Port U6) to expose a number of photoresists. Features as small as 0.25 microns have already been replicated suc- cessfully with high aspect ratios. The large increase in intensity of the storage ring over conventional X-ray sources should allow much greaterthroughput with simple resist processing. If the economic feasibil- ity of using synchrotron radiation for X-ray lithography is demonstrated at the NSLS, High aspect ratio replication of lest there could be a greatly expanded use of patterns in PMMA ohotoresist synchrotron radiation in the U.S. with stor- age rings becoming an integral part of semiconductor device factories. 1 /urn X-ray sar Microscopy (Port U15) On Port U15 of the VUV storage ring, a research team from the State University of New York at Stony Brook, in collaboration with the NSLS, has constructed a soft X-ray scanning microscope that is providing the first pictures of the internal structure of living cells in aqueous solutions while im- parting a minimal radiation dose. Pre- viously, electron microscopes have been employed to study cells. However, both the vacuum environment and the high radia- tion dose from the electrons prohibit the study of living cells, and destroy the cell's internal structure. Spatial resolutions on the 0.2 micron level have been achieved. With future improvements in resolution, and with the ability to locate the position of specific elements within a cell, this instru- ment may open up entirely new areas of biological research. Soft X-ray image ol single-celled diatom. Photoemission Spectroscopy 6000 (Ports U1?U35U4, On a large number of the UV beam lines, photoemission spectroscopy is utilized to look at the electronic structures of semi- 0.18 eV FWHM Photoelectron yield of CO (NATURAL WIDTH >0.1 eV) physisorbed on Au. In addition conductor and metal surfaces and to study to the main transition from the photoionization process of gases. There is o carbon 1s level to the first unoc- considerable interest in the exciting energy o cupied orbital, three CO vibra- region up to and above the carbon K-edge tional levels are resolved. (photon energy = 285eV). In one of these experiments, on Port U7, soft X-ray excitation involving C 1s elec- trons in CO, as well as in aliphatic and aromatic hydrocarbons, has been found to result in ionic fragmentation of the original molecule. The fragmentation pattern changes depending on whetner the C1s 286 2B7 288 289 electron is ionized orexcited into a Rydberg- PHOTON ENERGY (eV) like orbital, or into an unfilled molecular orbital. In this experiment, the near edge C 1s absorption spectra were correlated with the observation of specific ionic frag- ments of the original molecules. than 0.2eV can be achieved at the C 1s First results from a 6m/1 Om toroidal grat- edge. This resolution will enable studies of ing monochromatoron Port U8 (IBM) have the vibrational and chemical fine structure d3monstrated hat a resolution of better of core levels in organic compounds. 10 Dynamic Dichroism Spectroscopy (Port U9) (Port U9) Circular dichroism and absorption spec- Experiments on this port have demon- tra of poly (dl-dC) • poly (dl-dC) have been strated capabilities for gas and liquid phase recorded in the far UV and in the VUV (A > excitation spectra and lifetimes. 200nm) regions using synchrotron radia- The strong, continuous spectral range of tion from the 750 MeV storage ring. Al- s1. r.'hrotron radiation has also been util- though the far UV CD is qualitatively sim- ized to investigate the photoconductivity of ilar to the left-handed Z form of poly organic solutes in nonpolar solvents. This (dG-dC) • poly (dG-dC), the VUV spectra is provides informaticn about molecular polar- totally different and is, instead, similar to ization energies. Previous work has been the spectra of the right-handed A-and B- limited to molecules with low ionization forms of natural and synthetic DNA's. Thus, potentials, because appropriate light the VUV spectra appears to give better sources for the wavelength region below agreement with X-ray fiber diffraction data 200 nm have not been available. Photo- than conventional far UV CD. conductivity foresholds (directly related to polarization energies) have been deter- mined for anthracene, 1,2-benzanthracene, azulene, perylone, triphenylamine, and diaz- abicycloocta'c. The results indicate that solvent reorganization around the ion is not an important factor in the polarization energy. Som° of the above compounds, in liquid hydrogen solvents with high thermal electron mobilities, exhibit photoconduc- tivity spectra with unusual structure (i.e., Participants on the NSLS-HFBR support program several shoulders or maxima). The ener- taking data on port U9B. gies of these correspond to previously ob- 11 served Rydberg transitions in the gas 1300 i— > SYNCHROTRON RADIATION phase. This fact, together with dramatic PULSE solvent effects on the spectra and quantum yields, leads to the conclusion that for molecules such as anthracene, phoioioni- zation in solution takes place via the initial 1040 - formation of Rydberg states. The figure on the right shows data which represent the time evolution of fluores- cence from cyclohexane upon exposure to synchrotron radiation. Three curves are displayed: the data obtained by single- CO photon time correlation spectroscopy, a z double exponential fit to the data super- posed on it, and the time response function I of the counting system as determined by scattered synchrotron radiation. Excitation takes place at 174 nm, and fluorescence is collected between 210and 240 nm, defined by an interference filter between the sam- 260 ple and the photomultiplier. CHANNELS Cyclohexane (C6H12J Fluorescence at 230 nm. Excited at 174 nm. 12 ^ liminary examinations of the atomic oxy- Gas Phase gen and chlorinespectra, and an extension of the photoionization excitation functions Spectroscopy oftheparentandfragment ionsof COSand ENERGY (eV) C-S2 down to 350A. For the dimers AR2 and 29.0 28.5 28.0 27.5 27.0 26.5 i i i i (Port U11) Kra, and the trimer Ar3, photoionization 3s—»-np excitation functions at wavelengths less 98 7 6 5 4 _ Photoionization processes in the valence than 600 A were measured for the first time. shells of atoms and molecules in the gas- These excitation functions display molecu- \ IT phase can be studied on this beam line. lar Rydberg series that are closely asso- Experiments have been conducted on di- ciated with the corresponding atomic Ryd- ( • mers, trimers and larger clusters of argon, ts ) berg series and can be understood in a ir krypton and xenon. There have been pre- simple molecular orbital picture. wsrfv \j y \ \ .n y i m Z \ o n i o 2 •, Ia. 5) z o - V'' V «— i i i 424 432 440 448 456 464 472 WAVELENGTH (A) Photoionization spectra ol An, Ar2, Ars. Positions o! 3s -np atomic resonances are shown above spectra. Beam Line U11. 13 Free electron laser undulator alter installation in VUV storage ring straight section. Free electron laser undulator showing S1T1C05 permanent magnet structure. 14 General users are able to perform exper- dents will bfl trained in one of the diverse iments on an NSLS general user beam line scientific fields represented at the NSLS or on a commissioned PRT beam line and HFBR. The program is designed to which is available for use at least 25% of its defray expenses incurred during explora- total operational time. General user VUV tory visits to BNL, and while conducting proposals were first solicited in April, 1983 experiments at the NSLS and HFBR. It is and are presently being accepted without aimed at university users having only lim- any fixed submission deadlines. General ited grant support for their research. user X-ray proposals will be solicited after More detailed information on NSLS beam the first X-ray beam lines are commis- line instrumentation and user facilities is sioned. These proposals are reviewed by contained in "NSLS General Information members of the NSLS Program Advisory and Beam Line Instrumentation." Scient- Committee and then scheduled. ists wishing to obtain this guide, general If general users or PRTs usethe NSLSfor user proposal forms, NSLS-HFBR applica- proprietary research, a full cost recovery- tion forms or further information should fee will be charged for the amount of beam contact Dr. Roger Klaffky at: time utilized for proprietary research. The DOE has granted a class waiver of its f NSLS rights to inventions arising rom the use of Building 510E the NSLS and other DOE facilities by or for Brookhaven National Laboratory third party sponsors. ••^, Upton, New York11973 A limited amount of funds are available "~~~~~~ (516)282-4974 to general users under an NSLS-HFBR (516) 282-7114 Faculty and Student Support Program. The objective of this program is to make the exciting research capabilities at the NSLS and HFBFt accessible to scientists from U.S. institutions of higher education who will have occasion to use these facilities to complement the research program at their home institution. Most of the scientists par- ticipating in the program will be members of faculty/student groups in which stu- 15 Expansion of the NSLS An NSLS Phase 11 expansion project was formally reviewed and approved in July, SC WIGGLER 1983. Phase II is a three year, $19.7 million BEAM LINE (X17) project involving the development and instal- lation of special beam lines tied to state-of- the-art undulator and insertion devices. Phase II conventional construction will expand the existing NSLS building to pro- vide additional user laboratory and support areas and to house the entire NSLS staff in a common building. HIGH Q RESOLUTION SCATTERING BEAM LINE (X25) SOFT X-RAY IMAGING/ SPECTROSCOPY BEAM LINE {XI) TOK/SOFT X-RAY BEAM LINE (U13) HIGH E RESOLUTION INELASTIC X-RAY SCATTERING (X21) 16 Transportation Long Island MacArthur Airport, located Transportation between the Laboratory in nearby Islip, provides direct flights to and the Patchogue railroad station, or and from several East Coast cities, Chi- MacArthur (Islip) Airport may be provided cago and Pittsburgh. Long Island Limou- if no overtime is involved and requests sine and Winston Limousine provide ser- (which must havethe approval of the Depart- vice between the Laboratory and the New ment Chairman) have been made in ad- York City airports. A Long Island Railroad vance by calling the Transportation Office train leaves New York (Penn Station) Mon- (Ext. 2535). Transportation is not provided day through Friday at about 8:40 a.m. and to Kennedy or LaGuardia Airports. arrives in Patchcgue at about 10:16 a.m where visitors are met by a Laooratory bus. The train also stops at Jamaica (the station closest to John F. Kennedy and LaGuardia Airports) at about 8:57 a.m. Sincethe Long island Railroad schedule changes season- ally, the exact departure time should be checked, A Laboratory vehicle leaves the Public Relations Office (Building 134) at 4:20 p.m. on working days to transport travelers to the Mastic-Shirley railroad station. The train to New York City arrives at Penn Sta- tion about 6:30 p.m. Please make advance reservations by calling 516-282-2345 (FTS 666-2345). 18 w>iMii1 Si si 1 ill I S £ < Ul o? •« -I c? 2s 5j r;5 I-1 \ It. IIL. HO O s a g 1 i 1 s < I ) i* r i- BNL 34710 Editor: R.W. Klaffky BROOKHAVEN NATIONAL LABORATORY Uptcn, Long Island, New York 11973 UNDER CONTRACT NO. DE-AC02-76CH00016 WITH THE UNITED STATES DEPARTMENT OF ENERGY This report was prepared as an account of work sponsored by an agency of the United States Government. Neither the United States Government nor any agency thereof, nor any of the employees, nor any of the contractors, subcontractors, or their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process dis- closed, or represents that its use would not infringe privately owned rights. Reference herein to any spe- cific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise, does not necessarily constitute or imply its endor- sement, recommendation, or favoring by the United States Government or any agency, contractor or subcontractor thereof. The views and opinions of authors expressed herein do not necessarily state or reflect those of the United States Government or any agency, contractor or subcontractor thereof. The printing cost of this document was partially funded by Exxon Corporation using non-Depart- ment of Energy funds. •ft US. GO'. ^RNMENT PRINTING OFFICE: I 984 — JACKET NO: 7 1 9-309