121985848
Inelastic diffractive scattering at the CERN ISR
ONLY ELASTIC CROSS SECTIONS ENCODED.
THIS RECORD IS ONE OF 11 WHICH HAVE BEEN BROKEN INTO SMALLER UNITS. SQRT(S)=23 TO 38 GEV. 0.3& lt;PT& lt;1.7,0.6& lt;X& lt;1.0,0.15& lt;ITI& lt;3.25 CERN-HOLLAND-BRITISH COLLAB.
THIS RECORD IS ONE OF 11 WHICH HAVE BEEN BROKEN INTO SMALLER UNITS. SQRT(S)=23 TO 38 GEV. 0.3& lt;PT& lt;1.7,0.6& lt;X& lt;1.0,0.15& lt;ITI& lt;3.25 CERN-HOLLAND-BRITISH COLLAB.
THIS RECORD IS ONE OF 11 WHICH HAVE BEEN BROKEN INTO SMALLER UNITS. SQRT(S)=23 TO 38 GEV. 0.3& lt;PT& lt;1.7,0.6& lt;X& lt;1.0,0.15& lt;ITI& lt;3.25 CERN-HOLLAND-BRITISH COLLAB.
THIS RECORD IS ONE OF 11 WHICH HAVE BEEN BROKEN INTO SMALLER UNITS. SQRT(S)=23 TO 38 GEV. 0.3& lt;PT& lt;1.7,0.6& lt;X& lt;1.0,0.15& lt;ITI& lt;3.25 CERN-HOLLAND-BRITISH COLLAB.
THIS RECORD IS ONE OF 11 WHICH HAVE BEEN BROKEN INTO SMALLER UNITS. SQRT(S)=23 TO 38 GEV. 0.3& lt;PT& lt;1.7,0.6& lt;X& lt;1.0,0.15& lt;ITI& lt;3.25 CERN-HOLLAND-BRITISH COLLAB.
THIS RECORD IS ONE OF 11 WHICH HAVE BEEN BROKEN INTO SMALLER UNITS. SQRT(S)=23 TO 38 GEV. 0.3& lt;PT& lt;1.7,0.6& lt;X& lt;1.0,0.15& lt;ITI& lt;3.25 CERN-HOLLAND-BRITISH COLLAB.
THIS RECORD IS ONE OF 11 WHICH HAVE BEEN BROKEN INTO SMALLER UNITS. SQRT(S)=23 TO 38 GEV. 0.3& lt;PT& lt;1.7,0.6& lt;X& lt;1.0,0.15& lt;ITI& lt;3.25 CERN-HOLLAND-BRITISH COLLAB.
THIS RECORD IS ONE OF 11 WHICH HAVE BEEN BROKEN INTO SMALLER UNITS. SQRT(S)=23 TO 38 GEV. 0.3& lt;PT& lt;1.7,0.6& lt;X& lt;1.0,0.15& lt;ITI& lt;3.25 CERN-HOLLAND-BRITISH COLLAB.
THIS RECORD IS ONE OF 11 WHICH HAVE BEEN BROKEN INTO SMALLER UNITS. SQRT(S)=23 TO 38 GEV. 0.3& lt;PT& lt;1.7,0.6& lt;X& lt;1.0,0.15& lt;ITI& lt;3.25 CERN-HOLLAND-BRITISH COLLAB.
THIS RECORD IS ONE OF 11 WHICH HAVE BEEN BROKEN INTO SMALLER UNITS. SQRT(S)=23 TO 38 GEV. 0.3& lt;PT& lt;1.7,0.6& lt;X& lt;1.0,0.15& lt;ITI& lt;3.25 CERN-HOLLAND-BRITISH COLLAB.
THIS RECORD IS ONE OF 11 WHICH HAVE BEEN BROKEN INTO SMALLER UNITS. SQRT(S)=23 TO 38 GEV. 0.3& lt;PT& lt;1.7,0.6& lt;X& lt;1.0,0.15& lt;ITI& lt;3.25 CERN-HOLLAND-BRITISH COLLAB.
115609427
VIIth Blois Workshop summary: experimental
The Blois Workshop has become a conference not just restricted to diffractive scattering, but including topics such as searches for SUSY and Higgs, measurements of the top mass and b-decays. I will mention these briefly but will mostly discuss new results (and needed future measurements) in hard diffraction at HERA and the Tevatron.
59382161
QCD subgroup on diffractive and forward physics
Over the last few years, there has been a resurgence of interest in small-x or diffractive physics. This has been due to the realization that perturbative QCD techniques may be applicable to what was previously thought of as a non-perturbative problem and to the opening up of new energy regimes at HERA and the Tevatron collider. The goal is to understand the pomeron, and hence the behavior of total cross sections, elastic scattering and diffractive excitation, in terms of the underlying theory, QCD. This paper is divided into experiments of hadron-hadron colliders and electron-proton colliders.
118601539
Quartz Cherenkov counters for fast timing: QUARTIC
We have developed particle detectors based on fused silica (quartz) Cherenkov radi- ators read out with microchannel plate photomultipliers (MCP-PMTs) or silicon photomultipliers (SiPMs) for high precision timing (st 10-15 ps). One application is to measure the times of small angle protons from exclusive reactions, p+ p! p+ X + p, at the Large Hadron Collider, LHC. They may also be used to measure directional particle fluxes close to external or stored beams. The detectors have small areas (cm 2 ), but need to be active very close ( 4 mm) to the intense LHC beam, and so must be radiation hard and nearly edgeless. We present results of tests of detectors with quartz bars inclined at the Cherenkov angle, and with bars in the form of an "L" (with a 90 corner). We also describe a possible design for a fast timing hodoscope with few mm 2 elements.
82550552
Search for stable particles of charge 1 and mass deuteron mass
In a search for stable massive particles of charge q ⩾ 1 at the CERN ISR (√s = 53 GeV) no new particle in the mass range q × 2.4 GeV < m ≲ 30 GeV has been found among 3.1 × 107 recorded secondaries. At x = 2pL/√s = 0.21 and pT = 0.21 GeV/c the deuteron to π+ ratio is (1.3±0.2) × 10−4 and the antideuteron to π− ratio is (7.6±2.3) × 10−6. for (anti)tritons upper limits of (t/π+) < 5 × 10−7and (t/π−7) < 5 × 10−7 have been obtained.
126196482
ELASTIC SCATTERING OF POSITIVE KAONS ON POLARIZED PROTONS BETWEEN 0.87 AND 2.74 GeV/c. RESULTS AND PHASE-SHIFT ANALYSIS.
Abstract Polarization and differential cross-section data at 16 momenta between 0.86 and 2.74 GeV/ c are presented. (Preliminary data on some of the momenta have been published earlier.) In an energy-independent phase-shift analysis from threshold up to 2.5 GeV/ c , resonant-like as well as non-resonant solutions are found for the P 3 wave. An helicity flip-non-flip decomposition of the partial waves partly supports the indications found in the analyses of other reactions that the pomeron is built up mainly from s -channel helicity non-flip contributions.
16941683
Microlensing Constraints on the Frequency of Jupiter-Mass Companions: Analysis of 5 Years of PLANET Photometry
We analyze 5 years of PLANET photometry of microlensing events toward the Galactic bulge to search for the short-duration deviations from single-lens light curves that are indicative of the presence of planetary companions to the primary microlenses. Using strict event-selection criteria, we construct a well-defined sample of 43 intensively monitored events. We search for planetary perturbations in these events over a densely sampled region of parameter space spanning two decades in mass ratio and projected separation, but find no viable planetary candidates. By combining the detection efficiencies of the events, we find that, at 95% confidence, less than 25% of our primary lenses have companions with mass ratio q = 10-2 and separations in the lensing zone, [0.6-1.6]θE, where θE is the Einstein ring radius. Using a model of the mass, velocity, and spatial distribution of bulge lenses, we infer that the majority of our lenses are likely M dwarfs in the Galactic bulge. We conclude that less than 33% of M dwarfs in the Galactic bulge have companions with mass mp = MJ between 1.5 and 4 AU, and less than 45% have companions with mp = 3MJ between 1 and 7 AU, the first significant limits on planetary companions to M dwarfs. We consider the effects of the finite size of the source stars and changing our detection criterion, but find that these do not alter our conclusions substantially.
2974286
First microlens mass measurement: Planet photometry of EROS BLG-2000-5
We analyze PLANET photometric observations of the caustic-crossing binary lens microlensing event, EROS BLG-2000-5, and find that modeling the observed light curve requires incorporation of the microlens parallax and the binary orbital motion. The projected Einstein radius (E = 3.61 ± 0.11 AU) is derived from the measurement of the microlens parallax, and we are also able to infer the angular Einstein radius (θE = 1.38 ± 0.12 mas) from the finite source effect on the light curve, combined with an estimate of the angular size of the source given by the source position in a color-magnitude diagram. The lens mass, M = 0.612 ± 0.057 M☉, is found by combining these two quantities. This is the first time that parallax effects are detected for a caustic-crossing event and also the first time that the lens mass degeneracy has been completely broken through photometric monitoring alone. The combination of E and θE also allows us to conclude that the lens lies in the near side of the disk, within 2.6 kpc of the Sun, while the radial velocity measurement indicates that the source is a Galactic bulge giant.
15471874
The Frequency of Binary Stars in the Core of 47 Tucanae
Differential time series photometry has been derived for 46,422 main-sequence stars in the core of 47 Tucanae. The observations consisted of near-continuous 160 s exposures alternating between the F555W and F814W filters for 8.3 days in 1999 July with the Wide Field Planetary Camera 2 on the Hubble Space Telescope. Using Fourier and other search methods, 11 detached eclipsing binaries and 15 W Ursa Majoris stars have been discovered plus an additional 10 contact or near-contact noneclipsing systems. After correction for nonuniform area coverage of the survey, the observed frequencies of detached eclipsing binaries and W UMa stars within 90'' of the cluster center are 0.022% and 0.031%, respectively. The observed detached eclipsing binary frequency, the assumptions of a flat binary distribution with log period, and assuming that the eclipsing binaries with periods longer than about 4 days have essentially their primordial periods imply an overall binary frequency of 13% ± 6%. The observed W UMa frequency and the additional assumptions that W UMa stars have evolved to contact according to tidal circularization and angular momentum loss theory and that the contact binary lifetime is 109 yr imply an overall binary frequency of 14% ± 4%. An additional 71 variables with periods from 0.4 to 10 days have been found, which are likely to be BY Draconis stars in binary systems. The radial distribution of these stars is the same as that of the eclipsing binaries and W UMa stars and is more centrally concentrated than average stars but less so than the blue straggler stars. A distinct subset of six of these stars falls in an unexpected domain of the color-magnitude diagram, comprising what we propose to call red stragglers.
20954769
MOA-2009-BLG-387Lb: A massive planet orbiting an M dwarf
Aims. We report the discovery of a planet with a high planet-to-star mass ratio in the microlensing event MOA-2009-BLG-387, which exhibited pronounced deviations over a 12-day interval, one of the longest for any planetary event. The host is an M dwarf, with a mass in the range 0.07 M_⊙ < M_(host) < 0.49 M_⊙ at 90% confidence. The planet-star mass ratio q = 0.0132 ± 0.003 has been measured extremely well, so at the best-estimated host mass, the planet mass is m_p = 2.6 Jupiter masses for the median host mass, M = 0.19 M_⊙. Methods. The host mass is determined from two “higher order” microlensing parameters. One of these, the angular Einstein radius θ_E = 0.31 ± 0.03 mas has been accurately measured, but the other (the microlens parallax πE, which is due to the Earth’s orbital motion) is highly degenerate with the orbital motion of the planet. We statistically resolve the degeneracy between Earth and planet orbital effects by imposing priors from a Galactic model that specifies the positions and velocities of lenses and sources and a Kepler model of orbits. Results. The 90% confidence intervals for the distance, semi-major axis, and period of the planet are 3.5 kpc < D_L < 7.9 kpc, 1.1 AU < a < 2.7 AU, and 3.8 yr < P < 7.6 yr, respectively.
16391684
A short, nonplanetary, microlensing anomaly: Observations and light-curve analysis of MACHO 99-BLG-47
We analyze PLANET and MACHO observations of MACHO 99-BLG-47, the first nearly normal microlensing event for which high signal-to-noise ratio data reveal a well-covered, short-duration anomaly. This anomaly occurs near the peak of the event. Short-duration anomalies near the peak of otherwise normal events are expected to arise both from extreme-separation (either very close or very wide), roughly equalmass binary lenses and from planetary systems. We show that the lens of MACHO 99-BLG-47 is in fact an extreme-separation binary, not a planetary system, thus demonstrating for the first time that these two important classes of events can be distinguished in practice. However, we find that the wide-binary and closebinary lens solutions fit the data equally well and cannot be distinguished even at D� 2 ¼ 1. This degeneracy is qualitatively much more severe than the one identified for MACHO 98-SMC-1 because the present degeneracy spans two rather than one dimension in the magnification field and does not require significantly different blending fractions. In the Appendix, we explore this result and show that it is related to the symmetry in the lens equation. Subject headings: binaries: general — gravitational lensing — planetary systems