10,223 research outputs found
Relativistic quantum motion of spin-0 particles under the influence of non-inertial effects in the cosmic string space-time
We study solutions for the Klein-Gordon equation with vector and scalar
potentials of the Coulomb types under the influence of non-inertial effects in
the space-time of topological defects. We also investigate a quantum particle
described by the Klein-Gordon oscillator in the background space-time generated
by a string. An important result obtained is that the non-inertial effects
restrict the physical region of the space-time where the particle can be
placed. In addition, we show that these potentials can form bound states for
the relativistic wave equation equation in this kind of background.Comment: arXiv admin note: text overlap with arXiv:1608.0669
Experience with the Open Source based implementation for ATLAS Conditions Data Management System
Conditions Data in high energy physics experiments is frequently seen as
every data needed for reconstruction besides the event data itself. This
includes all sorts of slowly evolving data like detector alignment, calibration
and robustness, and data from detector control system. Also, every Conditions
Data Object is associated with a time interval of validity and a version.
Besides that, quite often is useful to tag collections of Conditions Data
Objects altogether. These issues have already been investigated and a data
model has been proposed and used for different implementations based in
commercial DBMSs, both at CERN and for the BaBar experiment. The special case
of the ATLAS complex trigger that requires online access to calibration and
alignment data poses new challenges that have to be met using a flexible and
customizable solution more in the line of Open Source components. Motivated by
the ATLAS challenges we have developed an alternative implementation, based in
an Open Source RDBMS. Several issues were investigated land will be described
in this paper:
-The best way to map the conditions data model into the relational database
concept considering what are foreseen as the most frequent queries.
-The clustering model best suited to address the scalability problem.
-Extensive tests were performed and will be described.
The very promising results from these tests are attracting the attention from
the HEP community and driving further developments.Comment: 8 pages, 4 figures, 3 tables, conferenc
The role of the time gauge in the 2nd order formalism
We perform a canonical quantization of gravity in a second-order formulation,
taking as configuration variables those describing a 4-bein, not adapted to the
space-time splitting. We outline how, neither if we fix the Lorentz frame
before quantizing, nor if we perform no gauge fixing at all, is invariance
under boost transformations affected by the quantization.Comment: 4 pages, Proceedings of the II Stueckelberg Worksho
Detecting transit signatures of exoplanetary rings using SOAP3.0
CONTEXT. It is theoretically possible for rings to have formed around
extrasolar planets in a similar way to that in which they formed around the
giant planets in our solar system. However, no such rings have been detected to
date.
AIMS: We aim to test the possibility of detecting rings around exoplanets by
investigating the photometric and spectroscopic ring signatures in
high-precision transit signals.
METHODS: The photometric and spectroscopic transit signals of a ringed planet
is expected to show deviations from that of a spherical planet. We used these
deviations to quantify the detectability of rings. We present SOAP3.0 which is
a numerical tool to simulate ringed planet transits and measure ring
detectability based on amplitudes of the residuals between the ringed planet
signal and best fit ringless model.
RESULTS: We find that it is possible to detect the photometric and
spectroscopic signature of near edge-on rings especially around planets with
high impact parameter. Time resolution 7 mins is required for the
photometric detection, while 15 mins is sufficient for the spectroscopic
detection. We also show that future instruments like CHEOPS and ESPRESSO, with
precisions that allow ring signatures to be well above their noise-level,
present good prospects for detecting rings.Comment: 13 pages, 16 figures, 2 tables , accepted for publication in A&
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