4,155 research outputs found
Latest ATLAS results from Run 2
After the first LHC long shutdown with upgrades to the machine and the
detectors, since 2015 the ATLAS experiment recorded more than 30 fb-1 of
integrated luminosity of pp collision data at 13 TeV centre- of-mass energy.
The data collected to date, the detector and physics performance, and
measurements of Standard Model processes are reviewed briefly before
summarising the latest ATLAS results in the Brout- Englert-Higgs sector, where
substantial progress has been made since the discovery. Searches for physics
phenomena beyond the Standard Model are also summarized. These proceedings
reflect only a brief summary of the material presented at the conference.Comment: 9 pages, 6 figures, top201
The ATLAS upgrade program
After the first successful LHC run in 2010-2012, plans are actively advancing
for a series of upgrades leading eventually to about above times the
design-luminosity in about ten years. The larger luminosity will allow to
perform precise measurements of the just discovered Higgs boson and to continue
searching for new physics beyond the Standard Model. Coping with the high
instantaneous and integrated luminosity will be a great challenge for the ATLAS
detector and will require changes in most of the subsystems, specially those at
low radii and large pseudorapidity, as well as in its trigger architecture.
Plans to consolidate and, whenever possible, to improve the physics performance
of the current detector over the next decade are summarized in this paper.Comment: 8 pages, proceedings for LHCP201
The rf control and detection system for PACO the parametric converter detector
In this technical note the rf control and detection system for a detector of
small harmonic displacements based on two coupled microwave cavities (PACO) is
presented. The basic idea underlying this detector is the principle of
parametric power conversion between two resonant modes of the system,
stimulated by the (small) harmonic modulation of one system parameter. In this
experiment we change the cavity length applying an harmonic voltage to a
piezo-electric crystal. The system can achieve a great sensitivity to small
harmonic displacements and can be an interesting candidate for the detection of
small, mechanically coupled, interactions (e.g. high frequency gravitational
waves).Comment: 13 pages, 4 postscript figure
Parametric gravity wave detector
Since 1978 superconducting coupled cavities have been proposed as a sensitive
detector of gravitational waves. The interaction of the gravitational wave with
the cavity walls, and the esulting motion, induces the transition of some
energy from an initially excited cavity mode to an empty one. The energy
transfer is maximum when the frequency of the wave is equal to the frequency
difference of the two cavity modes. In 1984 Reece, Reiner and Melissinos built
a detector of the type proposed, and used it as a transducer of harmonic
mechanical motion, achieving a sensitivity to fractional deformations of the
order dx/x ~ 10^(-18). In this paper the working principles of the detector are
discussed and the last experimental results summarized. New ideas for the
development of a realistic gravitational waves detector are considered; the
outline of a possible detector design and its expected sensitivity are also
shown.Comment: 9 pages, 6 figures. Talk given at the Workshop on Electromagnetic
Probes of Fundamentals Physics, Erice (Italy), October 200
A detector of gravitational waves based on coupled microwave cavities
Since 1978 superconducting coupled cavities have been proposed as sensitive
detector of gravitational waves. The interaction of the gravitational wave with
the cavity walls, and the resulting motion, induces the transition of some
electromagnetic energy from an initially excited cavity mode to an empty one.
The energy transfer is maximum when the frequency of the wave is equal to the
frequency difference of the two cavity modes. In this paper the basic
principles of the detector are discussed. The interaction of a gravitational
wave with the cavity walls is studied in the proper reference frame of the
detector, and the coupling between two electromagnetic normal modes induced by
the wall motion is analyzed in detail. Noise sources are also considered; in
particular the noise coming from the brownian motion of the cavity walls is
analyzed. Some ideas for the developement of a realistic detector of
gravitational waves are discussed; the outline of a possible detector design
and its expected sensitivity are also shown.Comment: 29 pages, 12 eps figures. Typeset by REVTe
A detector of small harmonic displacements based on two coupled microwave cavities
The design and test of a detector of small harmonic displacements is
presented. The detector is based on the principle of the parametric conversion
of power between the resonant modes of two superconducting coupled microwave
cavities. The work is based on the original ideas of Bernard, Pegoraro, Picasso
and Radicati, who, in 1978, suggested that superconducting coupled cavities
could be used as sensitive detectors of gravitational waves, and on the work of
Reece, Reiner and Melissinos, who, {in 1984}, built a detector of this kind.
They showed that an harmonic modulation of the cavity length l produced an
energy transfer between two modes of the cavity, provided that the frequency of
the modulation was equal to the frequency difference of the two modes. They
achieved a sensitivity to fractional deformations of dl/l~10^{-17} Hz^{-1/2}.
We repeated the Reece, Reiner and Melissinos experiment, and with an improved
experimental configuration and better cavity quality, increased the sensitivity
to dl/l~10^{-20} Hz^{-1/2}. In this paper the basic principles of the device
are discussed and the experimental technique is explained in detail. Possible
future developments, aiming at gravitational waves detection, are also
outlined.Comment: 28 pages, 12 eps figures, ReVteX. \tightenlines command added to
reduce number of pages. The following article has been accepted by Review of
Scientific Instruments. After it is published, it will be found at
http://link.aip.org/link/?rs
Status of the ATLAS detector and its readiness for early BSM Physics
The general status of the ATLAS experiment at the LHC is reviewed. Particular emphasis is given to the results from the in situ commissioning of the detector using calibration and cosmics data taking. The commissioning period has
prepared ATLAS for the first beam injection in September 2008. Some results from the beam experience will be described. Finally, given the present knowledge of the detector performance, the readiness of the detector for early studies of Physics beyond the Standard Model will be discussed
Hate Date
This is a story about a man who revenge dates women for hire because he thinks women are only out to hurt men. Bryce has something of an allergic reaction anytime he tries to talk to a woman unless it is under a completely false pretense, in which case he is a woman\u27s worst nightmare: A charming, handsome, heartbreaker. His world gets turned upside down when Bryce, despite his affliction, falls in love with a woman and must undergo painful subterfuge techniques just to be around her. Can a relationship built on pain, survive? Will Bryce give up what he believes in for the love of a gender he\u27s hated his whole life? Is revenge worth it
Hate Date
This is a story about a man who revenge dates women for hire because he thinks women are only out to hurt men. Bryce has something of an allergic reaction anytime he tries to talk to a woman unless it is under a completely false pretense, in which case he is a woman\u27s worst nightmare: A charming, handsome, heartbreaker. His world gets turned upside down when Bryce, despite his affliction, falls in love with a woman and must undergo painful subterfuge techniques just to be around her. Can a relationship built on pain, survive? Will Bryce give up what he believes in for the love of a gender he\u27s hated his whole life? Is revenge worth it
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