arXiv subjects

J. Hauptman

Publications and source records attributed to J. Hauptman.

76 records · Page 5Linked to original sources

arXiv2012

SiPMs coated with TPB : coating protocol and characterization for NEXT

Silicon photomultipliers (SiPM) are the photon detectors chosen for the tracking readout in NEXT, a neutrinoless ββ decay experiment which uses a high pressure gaseous xenon time projection chamber (TPC). The reconstruction of event track and topology in this gaseous detector is a key handle for background rejection. Among the commercially available sensors that can be used for tracking, SiPMs offer important advantages, mainly high gain, ruggedness, cost-effectiveness and radio-purity. Their main drawback, however, is their non sensitivity in the emission spectrum of the xenon scintillation (peak at 175 nm). This is overcome by coating these sensors with the organic wavelength shifter tetraphenyl butadienne (TPB). In this paper we describe the protocol developed for coating the SiPMs with TPB and the measurements performed for characterizing the coatings as well as the performance of the coated sensors in the UV-VUV range.

physics.ins-det↗

arXiv2010

Summary of the Linear Collider Testbeam Workshop 2009 - LCTW09

This note summarises the workshop LCTW09 held between the 3.11.2009 and 5.11.2009 at LAL Orsay. The workshop was dedicated to discuss the beam tests in the years 2010 up to 2013 for detectors to be operated at a future linear electron positron collider. The document underlines the rich R&D program on these detectors in the coming years. Large synergies were identified in the DAQ and software systems. Considerable consolidation of resources are expected from the establishment of semi-permanent beam lines for linear collider detector R&D at major centres like CERN and FNAL. Reproducing a beam structure as foreseen for the International Linear Collider (ILC) would clearly enhance the value of the obtained beam test results. Although not ultimately needed for every research program, all groups would exploit such a feature if it is available.

physics.ins-det↗

arXiv2009

Beam Polarization at the ILC: the Physics Impact and the Accelerator Solutions

In this contribution accelerator solutions for polarized beams and their impact on physics measurements are discussed. Focus are physics requirements for precision polarimetry near the interaction point and their realization with polarized sources. Based on the ILC baseline programme as described in the Reference Design Report (RDR), recent developments are discussed and evaluated taking into account physics runs at beam energies between 100 GeV and 250 GeV, as well as calibration runs on the Z-pole and options as the 1TeV upgrade and GigaZ.

physics.acc-ph↗

arXiv1997

A Search for Very High Energy Neutrinos from Active Galactic Nuclei

We report the results of a search for neutrino-induced particle cascades using a deep ocean water Cherenkov detector. The effective mass of the detector, a string of seven 40 cm diameter photomultipliers at 5.2 m spacing, is found through simulation analysis to be surprisingly large: greater than 1 megaton of water at incident neutrino energies of 1 PeV. We find no evidence for neutrino-induced cascades in 18.6 hours of observation. Although the limit implied by this observation is the strongest yet for predictions of active galatic nuclei (AGN) neutrinos at energies above 100 TeV, perhaps the more intriguing result is that the power of these techniques can be exploited to test these AGN models in a relatively short time.

astro-ph↗