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1.
Robert P. Crease 《Physics in Perspective (PIP)》2008,10(4):438-467
The National Synchrotron Light Source (NSLS) was the first facility designed and built specifically for producing and exploiting
synchrotron radiation. It was also the first facility to incorporate the Chasman-Green lattice for maximizing brightness.
The NSLS was a $24-million project conceived about 1970. It was officially proposed in 1976, and its groundbreaking took place
in 1978. Its construction was a key episode in Brookhaven’s history, in the transition of synchrotron radiation from a novelty
to a commodity, and in the transition of synchrotron-radiation scientists from parasitic to autonomous researchers. The way
the machine was conceived, designed, promoted, and constructed illustrates much both about the tensions and tradeoffs faced
by large scientific projects in the age of big science. In this article, the first of two parts, I cover the conception, design,
and planning of the NSLS up to its groundbreaking. Part II, covering its construction, will appear in the next issue.
Robert P. Crease is a Professor in the Department of Philosophy of Stony Brook University in Stony Brook, New York, and historian
at Brookhaven National Laboratory. 相似文献
2.
R. J. Baxter 《Journal of statistical physics》1981,26(3):427-452
The hard hexagon model in statistical mechanics is a special case of a solvable class of hard-square-type models, in which certain special diagonal interactions are added. The sublattice densities and order parameters of this class are obtained, and it is shown that many Rogers-Ramanujan-type identities naturally enter the working.Supported in part by the National Science Foundation under Grant No. PHY-79-06376A01.Part of this work was performed while the author was a visiting professor at the Institute for Theoretical Physics, State University of New York, Stony Brook, New York 11794. 相似文献
3.
Robert P. Crease 《Physics in Perspective (PIP)》2009,11(1):15-45
This is the second part of a two-part article about the National Synchrotron Light Source (NSLS), the first facility designed
and built specifically for producing and exploiting synchrotron radiation. The NSLS,a $24-million project conceived about
1970 and officially proposed in 1976, had its groundbreaking in 1978. Its construction was a key episode in Brookhaven’s history,
in the transition of synchrotron radiation from a novelty to a commodity, and in the transition of synchrotron-radiation scientists
from parasitic to autonomous researchers. In this part I cover the construction of the NSLS.The story of its construction
illustrates many of the tensions and risks involved in building a large scientific facility in a highly politicized environment:
risking a facility’s quality by underfunding it versus asking for more funding and risking not getting it; focusing on meeting time and budget promises that risk compromising machine
performance versus focusing on performance and risking cancellation; and the pros and cons of a pragmatic versus an analytic approach to commissioning.
Robert P. Crease is a Professor in the Department of Philosophy of Stony Brook University in Stony Brook, New York, and historian
at Brookhaven National Laboratory. 相似文献
4.
Robert P. Crease 《Physics in Perspective (PIP)》2005,7(3):330-376
The story of ISABELLE, a colliding-beam accelerator conceived in 1971, officially approved in 1978, partially constructed,
and terminated in 1983, is an important episode in the history of post-World War II science in the United States.The events
surrounding its planning, construction, and termination reveal much about the ambitions, strategies, and tensions of American
high-energy physicists, their collaborations and rivalries, and the difficulties of funding and constructing a large scientific
facility in the age of Big Science. In this article, the first of two parts, I cover the period up to the beginning of construction
in 1978. I place ISABELLE in the context of the early history of colliders, outline the physics goals that motivated the machine,
and describe the research and motivations behind its innovative but ultimately problematic superconducting magnet design.
I cover the key technological and administrative steps that the laboratory took to get the project underway and steer it past
several review committees. I also treat some of the conflicts within the laboratory, and between Brookhaven and other laboratories,
especially Fermilab, that hampered the project.
Robert P. Crease is a Professor in the Department of Philosophy of Stony Brook University in Stony Brook, New York, and historian
at Brookhaven National Laboratory. 相似文献
5.
Arthur L. Schawlow 《Physics in Perspective (PIP)》2004,6(3):310-343
This interview covers Arthur Schawlows professional life from his days as a graduate student at the University of Toronto, through his work with Charles Townes at Columbia University, his work at the Bell Telephone Laboratories, and into his professorship at Stanford University.This interview with Arthur L. Schawlow is adapted from an interview conducted by Joan Lisa Bromberg on January 19,1984, at Stanford University. This interview is one of some 1,000 transcribed interviews available for study by scholars at the American Institute of Physics Center for History of Physics in College Park, Maryland. Requests for reprints should be directed to John S. Rigden, Department of Physics, Washington University, St.Louis, MO 63130, USA, e-mail: jrigden@aip.org 相似文献
6.
We trace the history of physics in Bristol, before and after the foundation of the University, describing the important locations
and events and contributions by notable individuals. As well as the Nobel prizewinners Paul Dirac, Cecil Powell, and Nevill
Mott, these include Arthur Tyndall, Charles Frank, Yakir Aharonov, and David Bohm.
For detailed historical material and personal reminiscences relating to the Bristol Physics Department, see the website <http://www.phy.bris.ac.uk/history.html>.
Michael Berry and Brian Pollard have been members of the theory group in the Physics Department of the University of Bristol
since the 1960s. 相似文献
7.
J.A. Nolen 《The European Physical Journal A - Hadrons and Nuclei》2002,13(1-2):255-261
There are several nuclear physics laboratories in North America that have on-going research using energetic and stopped radioactive
beams. These include the large ISOL-type programs ISAC at TRIUMF and HRIBF at Oak Ridge and the in-flight fragmentation program
at the NSCL of Michigan State University. There are also smaller, more specialized, programs using a variety of techniques
at the 88-inch cyclotron of Berkeley, ATLAS at Argonne, the Cyclotron Institute of Texas A&M University, the Nuclear Structure
Laboratory at Notre Dame University, and the Nuclear Structure Laboratory at SUNY/Stony Brook. There are also three projects
on the horizon in North America for new capabilities in both the near term and more distant future. The intensities of the
in-flight fragment beams at the NSCL will be increased dramatically very soon as the Coupled Cyclotron Project will be completed
and commissioned for research by mid-2001. A new project, ISAC-II, has been approved in Canada. For the longer term, the United
States is considering construction of a major new facility, the Rare Isotope Accelerator (RIA), which would have a very high-intensity
heavy-ion driver linac. The RIA facility is proposed to utilize both ISOL and in-flight production mechanisms.
Received: 1 May 2001 / Accepted: 4 December 2001 相似文献
8.
Intensive blue photoluminescence (PL) was observed at room temperature from the nanocrystalline-Si/SiO2 (nc-Si/SiO2) multilayers (MLs) obtained by thermal annealing of SiO/SiO2 MLs for the first time. By controlling the size of nc-Si formed in SiO sublayer from 3.5 to 1.5 nm, the PL peak blueshifts from 457 to 411 nm. Combining the analysis of TEM, Raman and absorption measurement, this paper attributes the blue PL to multiple luminescent centres at the interface of nc-Si and SiO2. 相似文献
9.
A. Borowiec M. MacKenzie G.C. Weatherly H.K. Haugen 《Applied Physics A: Materials Science & Processing》2003,76(2):201-207
The final state of the material resulting from laser irradiation of silicon using 130 fs pulses at 790 nm was studied using
a number of techniques including scanning and transmission electron microscopies, as well as atomic force microscopy. Structural
details and the level of damage to the nearby solid following irradiation were characterized and are discussed in the context
of recent dynamical studies.
Received: 28 September 2001 / Accepted: 3 March 2002 / Published online: 19 July 2002
RID="*"
ID="*"Department of Engineering Physics, McMaster University, Hamilton, Ontario, L8S 4M1, Canada
RID="**"
ID="**"Corresponding author. Fax: +1-905/521-2773, E-mail: borowia@mcmaster.ca
RID="***"
ID="***"Present address: Department of Physics and Astronomy, University of Glasgow, Glasgow, G12 8QQ, UK
RID="****"
ID="****"Department of Materials Science and the CEMD, McMaster University, Hamilton, Ontario, L8S 4M1, Canada
RID="*****"
ID="*****"Departments of Engineering Physics, and Physics and Astronomy, and the CEMD, McMaster University, Hamilton, Ontario,
L8S 4M1, Canada 相似文献
10.
We calculate the twisted supersymmetric determinants that are necessary for the study of the propagation of spinning strings on arbitrary orbifolds. We calculate the degeneration behaviour of multiloop amplitudes for twisted internal sectors. We use this to derive the spectrum of dimensions of twist fields.On leave of absence from Department of Physics, Princeton University, Princeton, New Jersey 08544, USA 相似文献
11.
T. Ino Y. ArimotoT. Yoshioka K. MishimaK. Taketani S. MutoH.M. Shimizu H. KiraY. Sakaguchi T. OkuK. Sakai T. ShinoharaJ. Suzuki H. OtonoH. Oide S. YamashitaS. Imajo H. FunahashiM. Yamada Y. IwashitaM. Kitaguchi M. HinoZ. Suzuki T. SanukiT. Seki K. HirotaK. Ikeda H. SatoY. Otake H. OhmoriT. Morishima T. Shima 《Physica B: Condensed Matter》2011,406(12):2424-2428
We measured the neutron beam polarization of the BL05/NOP (Neutron Optics and Physics) beamline at J-PARC with an accuracy of less than 10−3 using polarized 3He gas as a neutron spin analyzer. Precise polarimetry of the neutron beam is necessary to understand the beamline optics as well as for the asymmetry measurements of the neutron beta decay, which are planned in this beamline. 相似文献
12.
Conversion elecron spectroscopy has been an important part of the nuclear spectrocopy research at the Department of Physics of the University of Jyväskylä since the commissioning of the first cyclotron in the mid 1970s. At the IGISOL facility a specialiced conversion electron spectrometer ELLI was developed in the late 1980s. The first results with ELLI were obtained using the beams from the old MC-20 cyclotron to study newly discovered isotopes of refractory fission products. In the present K130 cyclotron laboratory ELLI has been utilized in many decay-spectroscopy experiments both neutron-deficient and neutron-rich side of the valley of stability. In the early 2000s the new JYFLTRAP ion trap system overthrew ELLI from its permanent place in the IGISOL beamline. Conversion electron spectroscopy has continued with the new Penning trap that has been used in in-trap electron spectroscopy tests and post-trap electron spectroscopy is foreseen. 相似文献
13.
Voytas P. A. Behr J. A. Ghosh A. Gwinner G. Orozco L. A. Simsarian J. E. Sprouse G. D. Xu F. 《Hyperfine Interactions》1996,97(1):527-534
The techniques of laser cooling and trapping now make it possible to observe large samples of stable atoms in a small volume at low temperature. This capability was recently extended to radioactive isotopes. This opens up new opportunities for the investigation of fundamental symmetries through measurements using radioactive atoms. In this paper we will discuss several fundamental measurements in atomic systems and how the ability to trap radioactive atoms will play an important role in improving the precision of such measurements. Measurements of the effects of the weak interaction are of particular note since they are becoming quite precise. In particular, we will describe in detail the system developed at Stony Brook to trap radioactive alkali atoms and measure weak interaction effects in francium isotopes. 相似文献
14.
V. Pascalutsa 《The European Physical Journal A - Hadrons and Nuclei》2003,16(2):149-153
The nearest-neighbor mass-spacing distribution of the meson and baryon spectrum (up to 2.5 GeV) is described by the Wigner surmise corresponding to the statistics of the Gaussian orthogonal ensemble of random matrix theory. This can be viewed as a manifestation of quantum chaos in hadrons.
Received: 30 September 2002 / Accepted: 21 November 2002 / Published online: 4 February 2003
RID="a"
ID="a"Present address: Department of Physics and Astronomy, Ohio University, Athens, OH 45701, USA; e-mail: vlad@phy.ohiou.edu
Communicated by G. Orlandini 相似文献
15.
1. Department of Technical Physics, Peking University, Beijing 100871, China;
2. Department of Physics, Peking University, Beijing 100871, China 相似文献
16.
J. W. Dolce B. Yang M. Saeed L. F. DiMauro G. Scoles 《Applied physics. B, Lasers and optics》1993,56(1):43-46
A short pulse, high energy, high repetition rate dye amplifier with superior conversion efficiency is reported. The dye amplifier is composed of three single-pass dye cells, longitudinally pumped by a frequency doubled 1 kHz Nd: YLF regenerative amplifier. The dye amplifier yields 3.5 ps, 150 J pulses at 595 nm, corresponding to a 12% conversion efficiency. The ASE is 1% or less, and the transverse mode quality is near-Gaussian.In absentia from the Department of Chemistry, Princeton University, Princeton, NJ 08544, USA 相似文献
17.
Satya Dev Verma 《Pramana》1977,9(1):79-85
Fragmentation cross-section of16O relativistic ions, at two different energies, was measured in CsI crystal. An experiment designed basically to study primary
cosmic ray nuclei, was exposed to monoenergetic beam of16O ions of bevatron. Fragmentation of the ions was observed in a two layer CsI target. Each CsI crystal was 1 inch thick.
The main energy of the beam was 2.1 GeV/nucleon. A subsidiary beam of 0.5 GeV/nucleon oxygen-ions was created for this experiment
alone. The number of fragmentations occurring in each crystal was used to obtain the total fragmentation cross-section at
these energies. The Bradt-Peters overlap parameter was derived from these cross-sections.
The experiment was designed and fabricated at the Department of Physics and Astronomy, Louisiana State University, Baton Rouge,
USA and was performed in the accelerator facilities of the University of California, Berkeley, Calif., USA. 相似文献
18.
Bulk heating of transparent materials using a high-repetition-rate femtosecond laser 总被引:7,自引:0,他引:7
C.B. Schaffer J.F. García E. Mazur 《Applied Physics A: Materials Science & Processing》2003,76(3):351-354
Femtosecond laser pulses can locally induce structural and chemical changes in the bulk of transparent materials, opening
the door to the three-dimensional fabrication of optical devices. We review the laser and focusing parameters that have been
applied to induce these changes and discuss the different physical mechanisms that play a role in forming them. We then describe
a new technique for inducing refractive-index changes in bulk material using a high-repetition-rate femtosecond oscillator.
The changes are caused by a localized melting of the material, which results from an accumulation of thermal energy due to
nonlinear absorption of the high-repetition-rate train of laser pulses.
Received: 21 November 2001 / Accepted: 9 July 2002 / Published online: 25 October 2002
RID="*"
ID="*"Corresponding author. Fax: +1-858/534-7697, E-mail: cschaffer@ucsd.edu
RID="**"
ID="**"Current address: University of California, San Diego, Department of Physics, La Jolla, CA 92 093, USA 相似文献
19.
John Greenberg 《Physics in Perspective (PIP)》2005,7(1):66-106
Nobel laureate William A. Fowler recalls his early education in physics; his part in the history of nuclear physics at the California Institute of Technology in the 1930s; parallel efforts elsewhere, particularly at Berkeley and the Department of Terrestrial Magnetism in Washington,D.C.; his contacts with J. Robert Oppenheimer; and his work with Charles C. Lauritsen and Tommy Lauritsen before and after World War II.John Greenberg received his Ph.D. degree from the University of Wisconsin and was Caltech research fellow in history from 1980–1984. The Editors were saddened to learn that he died while this interview was in press. Requests for reprints may be directed to Judith R. Goodstein, Institute Archives 015A-74, Caltech, Pasadena, CA 91125 USA; e-mail: jrg@caltech.edu. 相似文献
20.
T. Balaban 《Communications in Mathematical Physics》1985,102(2):255-275
We prove the ultraviolet stability for three-dimensional lattice gauge field theories. We consider only the Wilson lattice approximation for pure Yang-Mills field theories. The proof is based on results of the previous papers on renormalization group method for lattice gauge theories.Work partially supported by the National Science Foundation under Grant PHY 82-03669 and DMS 84-01989On leave of absence, Postal address: Department of Physics, Harvard University, Cambridge, MA 02138, USA 相似文献