7,605 research outputs found
Charmonium spectral functions in collision
We study the in-medium propagation of low-lying charmonium states: ,
(3686), and (3770) in a Au GeV collision. This energy
regime will be available for the PANDA experiment. The time evolution of the
spectral functions of the charmonium states is studied with a BUU type
transport model. We observe a substantial effect of the medium in the dilepton
spectrum.Comment: 6 pages, 4 figures, Presented at Excited QCD 2017, Sintra, Portuga
Photometry of SN 2002bo with template image subtraction
VRI photometry of the type Ia supernova 2002bo is presented. This SN exploded
in a dusty region of the host galaxy NGC 3190, thus, subtraction of a template
frame was necessary to obtain reliable photometry. We used a template frame of
NGC 3190 taken during the course of our galaxy imaging project, fortunately,
just a few days before SN 2002bo was discovered. The aim of this project is to
collect template frames of nearby galaxies that are potential hosts of bright
SNe. Subtraction of pre-SN images helped us to exclude the background light
contamination of the host galaxy. The maximum occurred at JD 2452346, with
maximal V brightness of 13.58. MLCS analysis led to T0(B)=JD 2452346.1 pm 0.8
(fiducial B-maximum), E(B-V)=0.24 pm 0.02, mu0=32.46 pm 0.06, Delta=-0.14 pm
0.04. E(B-V)=0.24(2) indicates a significant extinction in the host galaxy as
the galactic reddening is negligible toward NGC 3190. The accepted value of
Delta indicates that SN 2002bo was a slightly overluminous SN by about 0.14
relative to fiducial SN Type Ia. The distance turned out to be 31.0 pm 3 Mpc.
In addition, the heavily obscured SN 2002cv was also detected on the I frame
taken on JD 2452434 (June 8, 2002), and a variable star is found in the field,
very close to the host galaxy.Comment: accepted by Astronomy and Astrophysic
More frequencies of KUV 02464+3239
Preliminary results on KUV 02464+3239, a pulsating DA white dwarf are
presented. Located near the red edge of the DAV instability strip, KUV
02464+3239 shows large amplitude and long period pulsation modes. Up to now
only one mode was known from a 50-minute-long light curve. Our more extended
observations allowed the identification of three additional frequencies. The
presence of previously known harmonics were confirmed and weak subharmonics are
also noticeable at some parts of the light curve. This suggests the dominance
of nonlinear pulsation effects from time to time.Comment: 3 pages, 3 eps figures; has been accepted for publication in
Astronomische Nachrichten (Vol. 8, 2007), proceedings of the
British-Hungarian-French N+N+N Workshop for Young Researcher
Main-Belt Asteroids in the K2 Engineering Field of View
Unlike NASA's original Kepler Discovery Mission, the renewed K2 Mission will
stare at the plane of the Ecliptic, observing each field for approximately 75
days. This will bring new opportunities and challenges, in particular the
presence of a large number of main-belt asteroids that will contaminate the
photometry. The large pixel size makes K2 data susceptible to the effect of
apparent minor planet encounters. Here we investigate the effects of asteroid
encounters on photometric precision using a sub-sample of the K2 Engineering
data taken in February, 2014. We show examples of asteroid contamination to
facilitate their recognition and distinguish these events from other error
sources. We conclude that main-belt asteroids will have considerable effects on
K2 photometry of a large number of photometric targets during the Mission, that
will have to be taken into account. These results will be readily applicable
for future space photometric missions applying large-format CCDs, such as TESS
and PLATO.Comment: accepted for publication in AJ, 6 page
Torakalna hernijacija kralješnične moždine
Herniation of the spinal cord through a dural defect is a rather rare deformity and very easily misdiagnosed as retromedullary occult intraspinal arachnoid cyst or meningocele. The possible origin of the dural defect can be traumatic, iatrogenic or unknown, so in these cases, congenital with great probability. On the thoracal part of the spinal column it shows a rather characteristic and misleading appearance. The anomaly leads to progressive Brown-Sequard syndrome, and the case history can be extremely long. Surgical repair of the dural defect results in improvement, or even complete recovery, if performed in time. These are the facts that emphasize the importance of early diagnosis.Hernijacija kralježnične moždine kroz duralne defekte prilično je rijetka deformacija koja se vrlo lako pogrešno dijagnosticira kao retromedularna okultna intraspinalna arahnoidna cista ili kao meningokela. Uzrok duralnog defekta može biti traumatski, jatrogeni ili nepoznat, a u ovim je slučajevima vrlo vjerojatno prirođen. Torakalni dio kralježnice pokazuje prilično karakterističan izgled, no koji može zavarati. Poremećaj uzrokuje pojavu progresivnog Brown-Séquardova sindroma, a anamneza može biti izrazito dugotrajna. Ako se provede na vrijeme, kirurško zatvaranje duralnog defekta dovodi do poboljšanja, pa čak i do potpunog oporavka, .to upućuje na važnost rane dijagnoze
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