arXiv subjects

J. Jones

Publications and source records attributed to J. Jones.

26 records · Page 2Linked to original sources

arXiv2008

Prospects for a direct dark matter search using high resistivity CCD detectors

The possibility of using CCD detectors in a low threshold direct detection dark matter search experiment is discussed. We present the main features of the DECam detectors that make them a good alternative for such an experiment, namely their low noise and their large depleted volume. The performance of the DECam CCDs for the detection of nuclear recoils is discussed, and a measurement of the ionization efficiency for these events is presented. Finally the plans and expected reach for the CCD Experiment at Low Background (CELB) are discussed.

hep-ex↗

arXiv2007

A Search for SS Cyg Outburst Predictors

We report null results on a two year photometric search for outburst predictors in SS Cyg. Observations in Johnson V and Cousins I were obtained almost daily for multiple hours per night for two observing seasons. The accumulated data are put through various statistical and visual analysis techniques but fails to detect any outburst predictors. However, analysis of 102 years of AAVSO archival visual data led to the detection of a correlation between a long term quasi-periodic feature at around 1,000-2,000 days in length and an increase in outburst rate.

astro-ph↗

arXiv2005

A Study for a Tracking Trigger at First Level for CMS at SLHC

It is expected that the LHC accelerator and experiments will undergo a luminosity upgrade which will commence after several years of running. This part of the LHC operations is referred to as Super-LHC (SLHC) and is expected to provide beams of an order of magnitude larger luminosity (1035cm-2sec-1) than the current design. Preliminary results are presented from a feasibility study for a First Level Tracking Trigger for CMS at the SLHC using the data of the inner tracking detector. As a model for these studies the current CMS pixel detector with the same pixel size and radial distances from the beam has been used. Monte Carlo studies have been performed using the full CMS simulation package (OSCAR) and the occupancy of such a detector at SLHC beam conditions has been calculated. The design of an electron trigger which uses both the calorimeter energy depositions and the pixel data to identify isolated electrons and photons has been investigated. Results on the tracker occupancy and the electron trigger performance are presented

physics.ins-det↗

arXiv2005

A Pixel Detector for Level-1 Triggering at SLHC

We report on preliminary design studies of a pixel detector for CMS at the Super-LHC. The goal of these studies was to investigate the possibility of designing an inner tracker pixel detector whose data could be used for selecting events at the First Level Trigger. The detector considered consists of two layers of 20x50x10 um3 pixels at very close radial proximity from each other so that coincidences of hits between the two layers amount to a track transverse momentum (pT) cut. This cut reduces the large amount of low-momentum data expected at SLHC while keeping the tracking efficiency very high for the high pT tracks. Preliminary results on the performance of such a detector are presented.

physics.ins-det↗

arXiv2005

The CMS Tracker Readout Front End Driver

The Front End Driver, FED, is a 9U 400mm VME64x card designed for reading out the Compact Muon Solenoid, CMS, silicon tracker signals transmitted by the APV25 analogue pipeline Application Specific Integrated Circuits. The FED receives the signals via 96 optical fibers at a total input rate of 3.4 GB/sec. The signals are digitized and processed by applying algorithms for pedestal and common mode noise subtraction. Algorithms that search for clusters of hits are used to further reduce the input rate. Only the cluster data along with trigger information of the event are transmitted to the CMS data acquisition system using the S-LINK64 protocol at a maximum rate of 400 MB/sec. All data processing algorithms on the FED are executed in large on-board Field Programmable Gate Arrays. Results on the design, performance, testing and quality control of the FED are presented and discussed.

physics.ins-det↗

arXiv2005

Ultrahigh Energy Tau Neutrinos

We study ultrahigh energy astrophysical neutrinos and the contribution of tau neutrinos from neutrino oscillations, relative to the contribution of the other flavors. We show the effect of tau neutrino regeneration and tau energy loss as they propagate through the Earth. We consider a variety of neutrino fluxes, such as cosmogenic neutrinos and neutrinos that originate in Active Galactic Nuclei. We discuss signals of tau neutrinos in detectors such as IceCube, RICE and ANITA.

hep-ph↗

arXiv2004

Tracing Very High Energy Tau Neutrinos from Cosmological Distances in Ice

Astrophysical sources of ultrahigh energy neutrinos yield tau neutrino fluxes due to neutrino oscillations. We study in detail the contribution of tau neutrinos with energies above $10^6$ GeV relative to the contribution of the other flavors. We consider several different initial neutrino fluxes and include tau neutrino regeneration in transit through the Earth and energy loss of charged leptons. We discuss signals of tau neutrinos in detectors such as IceCube, RICE and ANITA.

hep-ph↗

arXiv2003

Tracing very high energy neutrinos from cosmological distances in ice

Astrophysical sources of ultrahigh energy neutrinos yield tau neutrino fluxes due to neutrino oscillations. We study in detail the contribution of tau neutrinos with energies above PeV relative to the contribution of the other flavors. We consider several different initial neutrino fluxes and include tau neutrino regeneration in transit through the Earth and energy loss of charged leptons. We discuss signals of tau neutrinos in detectors such as IceCube, RICE and ANITA.

hep-ph↗