14,603 research outputs found
Diffuse light in z~0.25 galaxy clusters: constraining tidal damage and the faint end of the Luminosity Function
The starlight coming from the intergalactic space in galaxy clusters and
groups witnesses the violent tidal interactions that galaxies experience in
these dense environments. Such interactions may be (at least partly)
responsible for the transformation of normal star-forming galaxies into passive
dwarf ellipticals (dEs). In this contribution we present the first systematic
study of the IntraCluster Light (ICL) for a statistically representative sample
(Zibetti et al. 2005), which comprises 683 clusters selected between z=0.2 and
0.3 from ~1500 deg^2 in the SDSS. Their ICL is studied by stacking the images
in the g-, r-, and i-band after masking out all galaxies and polluting sources.
In this way a very uniform background illumination is obtained, that allows us
to measure surface brightnesses as faint as 31 mag/arcsec^2 and to trace the
ICL out to 700 kpc from the central galaxy. We find that the local fraction of
light contributed by intracluster stars rapidly decreases as a function of the
clustercentric distance, from ~40% at 100 kpc to ~5% at 500 kpc. By comparing
the distribution and colours of the ICL and of the clusters galaxies, we find
indication that the main source of ICL are the stars stripped from galaxies
that plunge deeply into the cluster potential well along radial orbits. Thus,
if dEs are the remnants of these stripped progenitors we should expect similar
radial orbital anisotropies and correlations between the dE luminosity function
and the amount of ICL in different clusters. The diffuse emission we measure is
contaminated by faint unresolved galaxies: this makes our flux estimate depend
to some extent on the assumed luminosity function, but, on the other hand,
allows us to constrain the number of faint galaxies. Our present results
disfavour steep (alpha<-1.35) faint-end powerlaw slopes.Comment: 4 pages, 2 figures, use iauc.cls. Oral presentation to appear in the
proceedings of "IAU Colloquium 198 - Near-Field Cosmology with Dwarf
Elliptical Galaxies", Les Diablerets 14-18 March 2005, B. Binggeli and H.
Jerjen ed
Halos around edge-on disk galaxies in the SDSS
We present a statistical analysis of halo emission for a sample of 1047
edge-on disk galaxies imaged in five bands by the Sloan Digital Sky Survey
(SDSS). Stacking the homogeneously rescaled images of the galaxies, we can
measure surface brightnesses as deep as mu_r~31 mag/arcsec^2. The results
strongly support the almost ubiquitous presence of stellar halos around disk
galaxies, whose spatial distribution is well described by a power-law
, in a moderately flattened spheroid (c/a~0.6). The colour
estimates in g-r and r-i, although uncertain, give a clear indication for
extremely red stellar populations, hinting at old ages and/or non-negligible
metal enrichment. These results support the idea of halos being assembled via
early merging of satellite galaxies.Comment: 15 pages, 9 figures. Accepted for publication on MNRAS. Version with
full resolution images available at
http://www.mpa-garching.mpg.de/~zibetti/papers/halos_edgeon.pd
Eosinophilic ulcer of the tongue - Case report.
Eosinophilic ulcer of the oral mucosa is a rare, self-limiting, chronic and benign lesion of unknown pathogenesis that affects the oral mucosa. We present the case of a 65 year-old Caucasian female with a fivemonth history of a painful ulcer on the lateral side of her tongue. The ulcer was not adhered to the underlying structures and there was no evidence of regional lymph node involvement. Laboratory examinations and X-rays revealed no abnormalities. Topical treatments had been performed without any improvement. Histopathological examination showed an ulcerated surface and mixed inflammatory infiltrate with several eosinophils extending into the mucosa and submucosa. No cellular atypia was observed. Based on the patient-s history and mucosal biopsy, a final diagnosis of eosinophilic ulcer of the oral mucosa was made
Greenberger-Horne-Zeilinger paradoxes for many qudits
We construct GHZ contradictions for three or more parties sharing an
entangled state, the dimension d of each subsystem being an even integer
greater than 2. The simplest example that goes beyond the standard GHZ paradox
(three qubits) involves five ququats (d=4). We then examine the criteria a GHZ
paradox must satisfy in order to be genuinely M-partite and d-dimensional.Comment: 5 pages RevTe
Generating continuous variable quantum codewords in the near-field atomic lithography
Recently, D. Gottesman et al. [Phys. Rev. A 64, 012310 (2001)] showed how to
encode a qubit into a continuous variable quantum system. This encoding was
realized by using non-normalizable quantum codewords, which therefore can only
be approximated in any real physical setup. Here we show how a neutral atom,
falling through an optical cavity and interacting with a single mode of the
intracavity electromagnetic field, can be used to safely encode a qubit into
its external degrees of freedom. In fact, the localization induced by a
homodyne detection of the cavity field is able to project the near-field atomic
motional state into an approximate quantum codeword. The performance of this
encoding process is then analyzed by evaluating the intrinsic errors induced in
the recovery process by the approximated form of the generated codeword.Comment: 9 pages, 5 figure
Be Decay Anomaly and Light
In this proceedings, we discuss a light (17 MeV) solution to the anomaly
observed in the decay of Beryllium-8 by the Atomki collaboration. We detail an
anomaly free model with minimal particle content which can satisfy all other
experimental constraints with gauge couplings .Comment: Prepared for the 2019 EW session of the 54th Rencontres de Moriond,
talk presented by Simon Kin
Aluminum arsenide cleaved-edge overgrown quantum wires
We report conductance measurements in quantum wires made of aluminum
arsenide, a heavy-mass, multi-valley one-dimensional (1D) system. Zero-bias
conductance steps are observed as the electron density in the wire is lowered,
with additional steps observable upon applying a finite dc bias. We attribute
these steps to depopulation of successive 1D subbands. The quantum conductance
is substantially reduced with respect to the anticipated value for a spin- and
valley-degenerate 1D system. This reduction is consistent with
disorder-induced, intra-wire backscattering which suppresses the transmission
of 1D modes. Calculations are presented to demonstrate the role of strain in
the 1D states of this cleaved-edge structure.Comment: Submitted to Applied Physics Letter
Chronic bacterial prostatitis: efficacy of short-lasting antibiotic therapy with prulifloxacin (UnidroxÂź) in association with saw palmetto extract, lactobacillus sporogens and arbutin (LactorepensÂź)
Bacterial prostatitis (BP) is a common condition accounting responsible for about 5-10% of all prostatitis cases; chronic bacterial prostatitis (CBP) classified as type II, are less common but is a condition that significantly hampers the quality of life, (QoL) because not only is it a physical condition but also a psychological distress. Commonly patients are treated with antibiotics alone, and in particular fluoroquinolones are suggested by the European Urology guidelines. This approach, although recommended, may not be enough. Thus, a multimodal approach to the prolonged antibiotic therapy may be helpful.210 patients affected by chronic bacterial prostatitis were enrolled in the study. All patients were positive to Meares-Stamey test and symptoms duration wasâ>â3 months. The purpose of the study was to evaluate the efficacy of a long lasting therapy with a fluoroquinolone in association with a nutraceutical supplement (prulifloxacin 600 mg for 21 days and an association of Serenoa repens 320 mg, Lactobacillus Sporogens 200 mg, Arbutin 100 mg for 30 days). Patients were randomized in two groups (A and B) receiving respectively antibiotic alone and an association of antibiotic plus supplement.Biological recurrence at 2 months in Group A was observed in 21 patients (27.6%) and in Group B in 6 patients (7.8%). Uropathogens found at the first follow-up were for the majority Gram - (E. coli and Enterobacter spp.). A statistically significant difference was found at the time of the follow-up between Group A and B in the NIH-CPSI questionnaire score, symptoms evidence and serum PSA.Broad band, short-lasting antibiotic therapy in association with a nutritional supplement (serenoa repens, lactobacillus sporogens and arbutin) show better control and recurrence rate on patients affected by chronic bacterial prostatitits in comparison with antibiotic treatment alone.NCT02130713Date of trial Registration: 30/04/2014
On the Possibility of a Trans-Planckian Duality
We investigate the possibility of a trans-Planckian duality, which exchanges
a manifold of events (space-time), with a manifold of momenta
(energy-momentum). Gravity has a dual counter-part, that is, a geometric theory
defined on the manifold of momenta. We provide a mathematical framework that
can possibly realize this idea, and analyze its classical behaviour.Comment: 21 pages, 4 figure
- âŠ