1WHSP: an IR-based sample of ∼\sim1,000 VHE γ\gamma-ray blazar candidates

Blazars are the dominant type of extragalactic sources at microwave and at $\gamma$-ray energies. In the most energetic part of the electromagnetic spectrum (E>100GeV) a large fraction of high Galactic latitude sources are blazars of the High Synchrotron Peaked (HSP) type, that is BL Lac objects with synchrotron power peaking in the UV or in the X-ray band. HSP blazars are remarkably rare, with only a few hundreds of them expected to be above the sensitivity limits of currently available surveys. To find these very uncommon objects, we have devised a method that combines ALLWISE survey data with multi-frequency selection criteria. The sample was defined starting from a primary list of infrared colour-colour selected sources from the ALLWISE all sky survey database, and applying further restrictions on IR-radio and IR-X-ray flux ratios. Using a polynomial fit to the multi-frequency data (radio to X-ray) we estimated synchrotron peak frequencies and fluxes of each object. We assembled a sample including 992 sources, which is currently the largest existing list of confirmed and candidates HSP blazars. All objects are expected to radiate up to the highest $\gamma$-ray photon energies. In fact, 299 of these are confirmed emitters of GeV $\gamma$-ray photons (based on Fermi-LAT catalogues), and 36 have already been detected in the TeV band. The majority of sources in the sample are within reach of the upcoming Cherenkov Telescope Array (CTA), and many may be detectable even by the current generation of Cherenkov telescopes during flaring episodes. The sample includes 425 previously known blazars, 151 new identifications, and 416 HSP candidates (mostly faint sources) for which no optical spectra is available yet. The full 1WHSP catalogue is on-line at http://www.asdc.asi.it/1whsp/ providing a direct link to the SED building tool where multifrequency data can be easily visualised

Gaia Data Release 1. Cross-match with external catalogues - Algorithm and results

Although the Gaia catalogue on its own will be a very powerful tool, it is the combination of this highly accurate archive with other archives that will truly open up amazing possibilities for astronomical research. The advanced interoperation of archives is based on cross-matching, leaving the user with the feeling of working with one single data archive. The data retrieval should work not only across data archives, but also across wavelength domains. The first step for seamless data access is the computation of the cross-match between Gaia and external surveys. The matching of astronomical catalogues is a complex and challenging problem both scientifically and technologically (especially when matching large surveys like Gaia). We describe the cross-match algorithm used to pre-compute the match of Gaia Data Release 1 (DR1) with a selected list of large publicly available optical and IR surveys. The overall principles of the adopted cross-match algorithm are outlined. Details are given on the developed algorithm, including the methods used to account for position errors, proper motions, and environment; to define the neighbours; and to define the figure of merit used to select the most probable counterpart. Statistics on the results are also given. The results of the cross-match are part of the official Gaia DR1 catalogue.Comment: 18 pages, 8 figures. Accepted for publication by A&

Italica (Seville, Spain): use of local marble in Augustan age

This study concerns 51 marble finds made of \u201cCipollino verde\u201d coming from the ancient city of Italica (north of the modern city of Santiponce, 9 km NW of Seville, Spain), the earliest Roman settlement in Spain, founded in 206 B.C. The aim of this work was to determine their provenance from Greek and Italian quarries or from local quarries worked in the Iberian Peninsula. Thin-section optical microscopy, X-ray powder diffraction, bulk rock chemistry and O, C and Sr stable isotope analyses were carried out. Results were compared with literature data on \u201cCipollino verde\u201d marbles quarried in southern Euboea (Greece), Apuan Alps (Italy), Almer\ueda, Extremoz, Seville (Spain) and \uc9vora (Portugal). These comparisons indicated twenty-five marble samples consistent with an origin from Italy (Corchia and Arni districts, Apuan alps), twenty from Greece (Styra and Pyrgari districts, southern Euboea) and only six from Spain (Macael, Almer\ueda province)

Evaluating GAIA performances on eclipsing binaries. III. Orbits and stellar parameters for UW LMi, V432 Aur and CN Lyn

The orbits and physical parameters of three detached F and G-type eclipsing binaries have been derived combining Hipparcos H(P) photometry with 8480-8740 Ang ground-based spectroscopy, simulating the photometric+spectroscopic observations that the GAIA mission will obtain. Tycho B(T) and V(T) light curves are too noisy to be modeled for the three targets, and only mean Tycho colors are retained to constrain the temperature. No previous combined photometric+spectroscopic solution exists in literature for any of the three targets. Quite remarkably, CN Lyn turned out to be an equal masses F5 triple system. Distances from the orbital solutions agree within the astrometric error with the Hipparcos parallaxes.Comment: A&A, accepted in pres

Studying the evolution of AGB stars in the Gaia epoch

We present asymptotic giant branch (AGB) models of solar metallicity, to allow the interpretation of observations of Galactic AGB stars, whose distances should be soon available after the first release of the Gaia catalogue. We find an abrupt change in the AGB physical and chemical properties, occurring at the threshold mass to ignite hot bottom burning,i.e. $3.5M_{\odot}$. Stars with mass below $3.5 M_{\odot}$ reach the C-star stage and eject into the interstellar medium gas enriched in carbon , nitrogen and $^{17}O$. The higher mass counterparts evolve at large luminosities, between $3\times 10^4 L_{\odot}$ and $10^5 L_{\odot}$. The mass expelled from the massive AGB stars shows the imprinting of proton-capture nucleosynthesis, with considerable production of nitrogen and sodium and destruction of $^{12}C$ and $^{18}O$. The comparison with the most recent results from other research groups are discussed, to evaluate the robustness of the present findings. Finally, we compare the models with recent observations of galactic AGB stars, outlining the possibility offered by Gaia to shed new light on the evolution properties of this class of objects.Comment: 21 pages, 11 figure, 3 tables, accepted for publication in MNRAS (2016 July 11

Gaia Data Release 2. Cross-match with external catalogues - Algorithms and results

Context. Although the Gaia catalogue on its own is a very powerful tool, it is the combination of this high-accuracy archive with other archives that will truly open up amazing possibilities for astronomical research. The advanced interoperation of archives is based on cross-matching, leaving the user with the feeling of working with one single data archive. The data retrieval should work not only across data archives but also across wavelength domains. The first step for a seamless access to the data is the computation of the cross-match between Gaia and external surveys. Aims. We describe the adopted algorithms and results of the pre-computed cross-match of the Gaia Data Release 2 (DR2) catalogue with dense surveys (Pan-STARRS1 DR1, 2MASS, SDSS DR9, GSC 2.3, URAT-1, allWISE, PPMXL, and APASS DR9) and sparse catalogues (Hipparcos2, Tycho-2, and RAVE 5). Methods. A new algorithm is developed specifically for sparse catalogues. Improvements and changes with respect to the algorithm adopted for DR1 are described in detail. Results. The outputs of the cross-match are part of the official Gaia DR2 catalogue. The global analysis of the cross-match results is also presented.Comment: accepted for publication in A&A Gaia DR2 special issu

Ship it to Me!: Evaluating Interlibrary Loan Services for Distance Students

Starting in Fall 2013, St. John Fisher College\u27s Lavery Library began providing Interlibrary Loan services to doctoral students at its two recently established satellite campuses, the College of New Rochelle (CNR) and Onondaga Community College (OCC). Although students from both campuses received loans at their homes through UPS delivery, the campus\u27 locations originally resulted in two different return procedures: patrons affiliated with CNR returned items through UPS, while an OCC staff member collected return items and drove them back to our library. Although this model worked well at the beginning, an increase in requests and differences in procedure resulted in confusion among patrons and staff relating to communication, extremely overdue materials, and renewal policies. After one academic year, our library reassessed our procedures and policies to improve internal workflows, better serve our patrons, and align with ILL best practices. Knowing that consistency and excellent communication with patrons is vital to a successful resource sharing program, we began by streamlining procedures for both campuses to utilize UPS return shipping. We also changed internal workflows, retooled overdue notices and policies, and became more proactive in educating distance patrons about the policies and benefits of using ILL. Since incorporating these changes and increasing succinct communication, distance students have been more responsive and mindful of our relationship with other resource sharing libraries, and feedback has been very positive. In the upcoming year, we are implementing the more cost-effective UPS CampusShip into our workflow, expanding ILL to include distance faculty, and continuing to look for ways to better serve the needs of our patrons

The mysterious eruption of V838 Mon

V838 Mon is marking one of the most mysterious stellar outbursts on record. The spectral energy distribution of the progenitor resembles an under-luminous F main sequence star (at V=15.6 mag), that erupted into a cool supergiant following a complex and multi-maxima lightcurve (peaking at V=6.7 mag). The outburst spectrum show BaII, LiI and lines of several s-elements, with wide P-Cyg profiles and a moderate and retracing emission in the Balmer lines. A light-echo discovered expanding around the object helped to constrain the distance (d=790+/-30 pc), providing M_V=+4.45 in quiescence and M_V=-4.35 at optical maximum (somewhat dependent on the still uncertain E(B-V)=0.5 reddening). The general outburst trend is toward lower temperatures and larger luminosities, and continuing so at the time of writing. The object properties conflict with a classification within already existing categories: the progenitor was not on a post-AGB track and thus the similarities with the born-again AGB stars FG Sge, V605 Aql and Sakurai's object are limited to the cool giant spectrum at maximum; the cool spectrum, the moderate wind velocity (500 km/sec and progressively reducing) and the monotonic decreasing of the low ionization condition argues against a classical nova scenario. The closest similarity is with a star that erupted into an M-type supergiant discovered in M31 by Rich et al. (1989), that became however much brighter by peaking at M_V=-9.95, and with V4332 Sgr that too erupted into an M-type giant (Martini et al. 1999) and that attained a lower luminosity, closer to that of V838 Mon. M31-RedVar, V4332 Sgr and V838 Mon could be manifestations of the same and new class of astronomical objects.Comment: A&A, in pres