Software technologies for a prototype ATLAS DAQ Burckhart, D.; Jones, R.; Mapelli, L. ...
Computer Physics Communications,
05/1998, Volume:
110, Issue:
1-3
Journal Article, Conference Proceeding
Peer reviewed
The ATLAS collaboration has defined a set of user requirements for the back-end software subsystem within the context of the data acquisition and event filter prototype “−1” project. Based on these ...requirements, a number of evaluations have been performed on candidate technologies and techniques in the areas of configuration data storage (Objectivity ODBMS; Rogue Wave Tools.h++ for C++ object persistence), inter-process communication (Corba; MPI), dynamic object behaviour (Harel StateChart generator), graphical user interfaces (cross-platform GUI builder; Java AWT) and software integration (ACE operating-system interface). This paper describes the important requirements which lead to the selection of these technologies, the results obtained from the evaluations and how we intend to apply them to the design and implementation phases of the project.
The ASTEP (Antarctica Search for Transiting ExoPlanets) program was originally aimed at probing the quality of the Dome C, Antarctica for the discovery and characterization of exoplanets by ...photometry. In the first year of operation of the 40 cm ASTEP 400 telescope (austral winter 2010), we targeted the known transiting planet WASP-19b in order to try to detect its secondary transits in the visible. This is made possible by the excellent sub-millimagnitude precision of the binned data. The WASP-19 system was observed during 24 nights in May 2010. The photometric variability level due to starspots is about 1.8% (peak-to-peak), in line with the SuperWASP data from 2007 (1.4%) and larger than in 2008 (0.07%). We find a rotation period of WASP-19 of 10.7 +/- 0.5 days, in agreement with the SuperWASP determination of 10.5 +/- 0.2 days. Theoretical models show that this can only be explained if tidal dissipation in the star is weak, i.e. the tidal dissipation factor Q'star > 3.10^7. Separately, we find evidence for a secondary eclipse of depth 390 +/- 190 ppm with a 2.0 sigma significance, a phase consistent with a circular orbit and a 3% false positive probability. Given the wavelength range of the observations (420 to 950 nm), the secondary transit depth translates into a day side brightness temperature of 2690(-220/+150) K, in line with measurements in the z' and K bands. The day side emission observed in the visible could be due either to thermal emission of an extremely hot day side with very little redistribution of heat to the night side, or to direct reflection of stellar light with a maximum geometrical albedo Ag=0.27 +/- 0.13. We also report a low-frequency oscillation well in phase at the planet orbital period, but with a lower-limit amplitude that could not be attributed to the planet phase alone, and possibly contaminated with residual lightcurve trends.
The ANTARES telescope has the opportunity to detect transient neutrino sources, such as gamma-ray bursts (GRBs), core-collapse supernovae (SNe), flares of active galactic nuclei (AGNs)... To enhance ...the sensitivity to these sources, we are developing a new detection method based on the observation of neutrino bursts followed by an optical detection. The ANTARES Collaboration is implementing a fast on-line event reconstruction with a good angular resolution. These characteristics allow to trigger an optical telescope network in order to identify the nature of the neutrinos (and high energy cosmic-rays) sources. This follow-up can be done with a network of small automatic telescopes and required a small observation time. An optical follow-up of special events, such as neutrino doublets in coincidence in time and space or single neutrino having a very high energy, would not only give access to the nature of the sources but also improve the sensitivity for neutrino detection from SNe or GRBs.
Performance of the ATLAS electromagnetic calorimeter end-cap module 0 Ballansat, J; Bazan, A; Beaugiraud, B ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
2003, Volume:
500, Issue:
1
Journal Article
Peer reviewed
Open access
The construction and beam test results of the ATLAS electromagnetic end-cap calorimeter pre-production module 0 are presented. The stochastic term of the energy resolution is between 10% and
12.5%
...GeV
1/2
over the full pseudorapidity range. Position and angular resolutions are found to be in agreement with simulation. A global constant term of 0.6% is obtained in the pseudorapidity range 2.5<
η<3.2 (inner wheel).
Performance of the ATLAS electromagnetic calorimeter barrel module 0 Aubert, B.; Ballansat, J.; Beaugiraud, B. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
2003, Volume:
500, Issue:
1
Journal Article
Peer reviewed
Open access
The construction and performance of the barrel pre-series module 0 of the future ATLAS electromagnetic calorimeter at the LHC is described. The signal reconstruction and performance of ATLAS-like ...electronics has been studied. The signal to noise ratio for muons has been found to be 7.11±0.07. An energy resolution of better than
9.5%
GeV
1/2/
E
(sampling term) has been obtained with electron beams of up to
245
GeV
. The uniformity of the response to electrons in an area of Δ
η×Δ
φ=1.2×0.075 has been measured to be better than 0.8%.
Future in astroparticle physics and observational cosmology Carr, J.
Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment,
03/2007, Volume:
572, Issue:
1
Journal Article, Conference Proceeding
Peer reviewed
This article is based on an introductory presentation at the 10th Pisa Meeting on Frontier Detectors for Frontier Physics at Elba in May 2006. A sample of results and expected future advances in the ...field of astroparticle physics are presented.
The Dark Energy Spectroscopic Instrument (DESI) has embarked on an ambitious five-year survey to explore the nature of dark energy with spectroscopy of 40 million galaxies and quasars. DESI will ...determine precise redshifts and employ the Baryon Acoustic Oscillation method to measure distances from the nearby universe to z > 3.5, as well as measure the growth of structure and probe potential modifications to general relativity. In this paper we describe the significant instrumentation we developed for the DESI survey. The new instrumentation includes a wide-field, 3.2-deg diameter prime-focus corrector that focuses the light onto 5020 robotic fiber positioners on the 0.812 m diameter, aspheric focal surface. The positioners and their fibers are divided among ten wedge-shaped petals. Each petal is connected to one of ten spectrographs via a contiguous, high-efficiency, nearly 50 m fiber cable bundle. The ten spectrographs each use a pair of dichroics to split the light into three channels that together record the light from 360 - 980 nm with a resolution of 2000 to 5000. We describe the science requirements, technical requirements on the instrumentation, and management of the project. DESI was installed at the 4-m Mayall telescope at Kitt Peak, and we also describe the facility upgrades to prepare for DESI and the installation and functional verification process. DESI has achieved all of its performance goals, and the DESI survey began in May 2021. Some performance highlights include RMS positioner accuracy better than 0.1", SNR per \sqrtÅ > 0.5 for a z > 2 quasar with flux 0.28e-17 erg/s/cm^2/A at 380 nm in 4000s, and median SNR = 7 of the OII doublet at 8e-17 erg/s/cm^2 in a 1000s exposure for emission line galaxies at z = 1.4 - 1.6. We conclude with highlights from the on-sky validation and commissioning of the instrument, key successes, and lessons learned. (abridged)
A new combined test of an electromagnetic liquid argon accordion calorimeter and a hadronic scintillating-tile calorimeter was carried out at the CERN SPS. These devices are prototypes of the barrel ...calorimeter of the future ATLAS experiment at the LHC. The energy resolution of pions in the energy range from 10 to 300 GeV at an incident angle
θ of about 12° is well described by the expression
σ/E=((41.9±1.6)%/
E
+(1.8±0.1)%)⊕(1.8±0.1)/E
, where
E is in GeV. The response to electrons and muons was evaluated. Shower profiles, shower leakage and the angular resolution of hadronic showers were also studied. Results are compared with those from the previous beam test.
We present a search, using the Murchison Widefield Array (MWA), for electromagnetic counterparts to two candidate high energy neutrino events detected by the ANTARES neutrino telescope in 2013 ...November and 2014 March. These events were selected by ANTARES because they are consistent, within 0.4 degrees, with the locations of galaxies within 20 Mpc of Earth. Using MWA archival data at frequencies between 118 and 182 MHz, taken ~20 days prior to, at the same time as, and up to a year after the neutrino triggers, we look for transient or strongly variable radio sources consistent with the neutrino positions. No such counterparts are detected, and we set a 5 sigma upper limit for low-frequency radio emission of ~1E37 erg/s for progenitors at 20 Mpc. If the neutrino sources are instead not in nearby galaxies, but originate in binary neutron star coalescences, our limits place the progenitors at z > 0.2. While it is possible, due to the high background from atmospheric neutrinos, that neither event is astrophysical, the MWA observations are nevertheless among the first to follow up neutrino candidates in the radio, and illustrate the promise of wide-field instruments like MWA to detect electromagnetic counterparts to such events.
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