119081947
Venus transits: history and opportunities for planetary, solar and gravitational physics
The data of 2012 transit of Venus are compared with the ones of 2004. The thickness of the atmosphere of Venus, its aureole and the effect of oblateness and other asphericities in the figure of the Sun are taken into consideration, as well as the black drop effect. A new extrapolation method for the contact times is presented. The next Mercury transit in 2016 will be fully visible from Europe, and the data will be gathered in view of this new method of analysis, to obtain the solar diameter.
119255637
Geometrical information on the solar shape: high precision results with SDO/HMI
The uncertainty of measurement of solar diameter is depending on the observational time scale. Full-disc images of SDO/HMI and the images from ground observations in Huairou Solar Observing Station have been analyzed to get the values of solar diameter. The satellite observations reach a very high precision, but the absolute image scale still need to be calibrated. The solar oblateness is a more challenging measurement than the diameter, since the signal amplitude is a few milli-arcseconds. It is a relative measurement, then not affected by the pixel scale calibration required by the diameter measurement. But the results are strongly dependent on the state of instrument such as focus plane deformation and on the calculation process.
118481017
The power spectrum of the seeing during solar observations
Measurements of the power spectrum of the atmospheric seeing in the line of sight of the Sun, in the range 0.001-1 Hz, have been performed in Santa Maria degli Angeli Lucernaria Dome, at IRSOL and in Huairou Station. This study is aimed to understand the criticity of the meridian transits method for solar diameter monitoring.
119266512
Atmospheric fluctuations below 0.1 Hz during drift-scan solar diameter measurements
Measurements of the power spectrum of the seeing in the range 0.001–1 Hz have been
 performed in order to understand the criticity of the transits method for solar diameter
 monitoring.
118479131
Venus transit, aureole and solar diameter
The possibility to measure the solar diameter using the transits of Mercury has been exploited to investigate the past three centuries of its evolution and to calibrate these measurements made with satellites. This measurement basically consists to compare the ephemerides of the internal contact timings with the observed timings. The transits of Venus of 2004 and 2012 gave the possibility to apply this method, involving a planet with atmosphere, with the refraction of solar light through it creating a luminous arc all around the disk of the planet. The observations of the 2012 transit made to measure the solar diameter participate to the project Venus Twilight Experiment to study the aureole appearing around it near the ingress/egress phases.
120435997
High-pT hadronic trigger using electromagnetic calorimeter with the STAR detector
Abstract We derive a new method to improve the statistics of identified particles at high transverse momentum ( p T ) using online-triggered events by the STAR Barrel electro-magnetic-calorimeter (BEMC) detector. The BEMC is used to select charged hadrons ( π ± , K ± , and p ( p ¯ ) ) via hadronic shower energy deposited in the BEMC. With this trigger, the statistics of the high p T particles are significantly enhanced (by a factor of up to ∼ 100 for STAR) with trigger efficiency up to 20%. In addition, weak-decay V0s ( K S 0 and Λ ( Λ ¯ ) ) can be reconstructed by selecting the BEMC-trigger hadron as one of the decay daughters. We also show that the trigger efficiency can be obtained reliably in simulation and data-driven approaches, and final results from new method are compared with previous published results.
119230540
Quantitative extraction of the jet transport parameter from combined data at RHIC and LHC
Abstract Using theoretical tools developed by the JET Collaboration in which one employs ( 2 + 1 ) D or ( 3 + 1 ) D hydrodynamic models for the bulk medium evolution and jet quenching models, the combined data on suppression of single inclusive hadron spectra at both RHIC and LHC are systematically analyzed with five different approaches to the parton energy loss. The jet transport parameter is extracted from the best fits to the data with values of q ˆ ≈ 1.2 ± 0.3 and 1.9 ± 0.7 GeV 2 / fm in the center of the most central Au + Au collisions at s = 200 GeV and Pb + Pb collisions at s = 2.67 TeV , respectively, at an initial time τ 0 = 0.6 fm / c for a quark jet with an initial energy of 10 GeV/c.
122233645
THE ASSOCIATED PRODUCTION OF THE NEUTRAL TOP-PION WITH A PAIR OF THIRD FAMILY QUARKS AT THE HADRON COLLIDERS
We study the associated production of the neutral top-pion $(\Pi_t^0)$ with the third family quarks within the context of the topcolor-assisted technicolor model at the hadron colliders. The studies show that, at the Tevatron, the cross-sections of all these processes are too small to produce enough identified signals. But the cross-sections can be largely enhanced at the LHC. Specially for the processes $pp\rightarrow t\bar{t}\Pi_t^0$ and $pp\rightarrow t\bar{c}\Pi_t^0$, the cross-sections can reach the level of a few hundred fb even a few pb for the light neutral top-pion. With the high yearly luminosity 100 fb-1 at the LHC, over 104 signals can be produced via the above two processes. There exists an ideal flavor-changing mode to detect neutral top-pion, i.e. $\Pi_t^0\rightarrow t\bar{c}$, because the SM background of such production mode are very clean. Therefore, we can conclude that neutral top-pion should be observable at the LHC via the processes $pp\rightarrow t\bar{t}\Pi_t^0$ and $pp\rightarrow ...
123633000
The Higgs Boson Mass in MSM and the New Data
In this paper we study the implications of the top quark mass measurement at CDF for the Higgs boson mass . We find that the present data are most likely in favor of heavy Higgs boson, for , but no realistic constraints on could be derived until the measurement of reaches high precision.
119444267
High pT hadron–hadron correlations
We propose the formulation of a dihadron fragmentation function in terms of parton matrix elements. Under the collinear factorization approximation and facilitated by the cut-vertex technique, the two hadron inclusive cross section at leading order (LO) in e + e - annihilation is shown to factorize into a short distance parton cross section and the long-distance dihadron fragmentation function. We also derive the DGLAP evolution equation of this function at leading log. The evolution equation for the non-singlet and singlet quark fragmentation function and the gluon fragmentation function are solved numerically with the initial condition taken from event generators. Modifications to the dihadron fragmentation function from higher twist corrections in DIS off nuclei are computed. Results are presented for the cases of physical interest.