2,646 research outputs found

    Looking for Stars and Finding the Moon: Effects of Lunar Gamma-ray Emission on Fermi LAT Light Curves

    Full text link
    We are conducting a search for new gamma-ray binaries by making high signal-to-noise light curves of all cataloged Fermi LAT sources and searching for periodic variability using appropriately weighted power spectra. The light curves are created using a variant of aperture photometry where photons are weighted by the probability that they came from the source of interest. From this analysis we find that the light curves of a number of sources near the ecliptic plane are contaminated by gamma-ray emission from the Moon. This shows itself as modulation on the Moon's sidereal period in the power spectra. We demonstrate that this contamination can be removed by excluding times when the Moon was too close to a source. We advocate that this data screening should generally be used when analyzing LAT data from a source located close to the path of the Moon.Comment: 2012 Fermi Symposium proceedings - eConf C12102

    Type IIA embeddings of D=5D=5 minimal gauged supergravity via Non-Abelian T-duality

    Full text link
    In this note, we construct explicit Type IIA uplifts of D=5D=5 minimal gauged supergravity, by T-dualising known Type IIB uplifts on N5=S5N_5 = S^5, T1,1T^{1,1} and Yp,qY^{p,q} along their SU(2)SU(2) isometries. When the D=5D=5 gauge field is set to zero, our uplifts recover precisely the known non-Abelian T-duals of the AdS5×N5AdS_5\times N_5 solutions. As an application, we obtain new supersymmetric AdS3×Σ×M5AdS_3\times\Sigma\times M_5 solutions in Type IIA, where Σ=WCP[n,n+]1\Sigma = \mathbb{WCP}^1_{[n_-,n_+]} is a weighted projective space. Existing holographic results of T-dualised AdS solutions suggest that our solutions capture features of d=2d = 2 SCFTs with N=(0,2)\mathcal{N}=(0, 2) supersymmetry.Comment: 41 pages, 1 figur

    A new family of AdS4AdS_4 S-folds in type IIB string theory

    Full text link
    We construct infinite new classes of AdS4×S1×S5AdS_4\times S^1\times S^5 solutions of type IIB string theory which have non-trivial SL(2,Z)SL(2,\mathbb{Z}) monodromy along the S1S^1 direction. The solutions are supersymmetric and holographically dual, generically, to N=1\mathcal{N}=1 SCFTs in d=3d=3. The solutions are first constructed as AdS4×RAdS_4\times \mathbb{R} solutions in D=5D=5 SO(6)SO(6) gauged supergravity and then uplifted to D=10D=10. The solutions all arise as limiting cases of Janus solutions of d=4d=4, N=4\mathcal{N}=4 SYM theory which are supported both by a different value of the coupling constant on either side of the interface, as well as by fermion and boson mass deformations. As special cases, the construction recovers three known S-fold constructions, which preserve N=1,2\mathcal{N}=1,2 and 4 supersymmetry, as well as a recently constructed N=1\mathcal{N}=1 AdS4×S1×S5AdS_4\times S^1\times S^5 solution (not S-folded). We also present some novel "one-sided Janus" solutions that are non-singular.Comment: 54 pages, 13 figure

    Changes in racial and gender inequality since 1970

    Get PDF
    The decades following 1970 to the present were an important period because they marked an era in which measures such as Affirmative Action were introduced to improve opportunities for American minorities and women. Ironically, this also was a period when income inequality dramatically increased in the United States. We analyze Census data from 1970 to 2009 to assess whether inequality in the earnings received by women and minorities has changed in this period. We find a complicated set of results. Racial inequalities persist though to a lesser extent than they did four decades earlier. Asian workers in particular have seen improvements and a lessening of inequality relative to White workers. Gender inequality also persists, though more in some groups than others. Overall, the results of this study underscore the persistence of racial and gender inequality in the United States

    Optical Polarization and Spectral Variability in the M87 Jet

    Get PDF
    During the last decade, M87's jet has been the site of an extraordinary variability event, with one knot (HST-1) increasing by over a factor 100 in brightness. Variability was also seen on timescales of months in the nuclear flux. Here we discuss the optical-UV polarization and spectral variability of these components, which show vastly different behavior. HST-1 shows a highly significant correlation between flux and polarization, with P increasing from 20\sim 20% at minimum to >40% at maximum, while the orientation of its electric vector stayed constant. HST-1's optical-UV spectrum is very hard (αUVO0.5\alpha_{UV-O}\sim0.5, FνναF_\nu\propto\nu^{-\alpha}), and displays "hard lags" during epochs 2004.9-2005.5, including the peak of the flare, with soft lags at later epochs. We interpret the behavior of HST-1 as enhanced particle acceleration in a shock, with cooling from both particle aging and the relaxation of the compression. We set 2σ\sigma upper limits of 0.5δ0.5 \delta parsecs and 1.02cc on the size and advance speed of the flaring region. The slight deviation of the electric vector orientation from the jet PA, makes it likely that on smaller scales the flaring region has either a double or twisted structure. By contrast, the nucleus displays much more rapid variability, with a highly variable electric vector orientation and 'looping' in the (I,P)(I,P) plane. The nucleus has a much steeper spectrum (αUVO1.5\alpha_{UV-O} \sim 1.5) but does not show UV-optical spectral variability. Its behavior can be interpreted as either a helical distortion to a steady jet or a shock propagating through a helical jet.Comment: 14 pages, 7 figures, ApJ, in pres

    Higgs Messengers

    Full text link
    We explore the consequences of the Higgs fields acting as messengers of supersymmetry breaking. The hidden-sector paradigm in the gauge mediation framework is relaxed by allowing two types of gauge-invariant, renormalizable operators that are typically discarded: direct coupling between the Higgses and supersymmetry breaking singlets, and Higgs-messenger mixing terms. The most important phenomenological consequence is a flavor-dependent shift in sfermion masses. This is from a one-loop contribution, which we compute for a general set of weak doublet messengers. We also study a couple of explicit models in detail, finding that precision electroweak constraints can be satisfied with a spectrum significantly different from that of gauge mediation.Comment: 20 pages, 5 figure

    CRISPR Knockout of the HuR Gene Causes a Xenograft Lethal Phenotype.

    Get PDF
    Pancreatic ductal adenocarcinoma (PDA) is the third leading cause of cancer-related deaths in the United States, whereas colorectal cancer is the third most common cancer. The RNA-binding protein HuR (ELAVL1) supports a pro-oncogenic network in gastrointestinal (GI) cancer cells through enhanced HuR expression. Using a publically available database, HuR expression levels were determined to be increased in primary PDA and colorectal cancer tumor cohorts as compared with normal pancreas and colon tissues, respectively. CRISPR/Cas9 technology was successfully used to delete the HuR gene in both PDA (MIA PaCa-2 and Hs 766T) and colorectal cancer (HCT116) cell lines. HuR deficiency has a mild phenotype
    corecore