52,219 research outputs found
Probing the local environment of the supernova remnant HESS J1731-347 with CO and CS observations
No full textThe shell-type supernova remnant HESS J1731 − 347 emits TeV gamma-rays, and is a key object for the study of the cosmic ray acceleration potential of supernova remnants. We use 0.5–1 arcmin Mopra CO/CS(1–0) data in conjunction with HI data to calculate column densities towards the HESS J1731 − 347 region. We trace gas within at least four Galactic arms, typically tracing total (atomic+molecular) line-of-sight H column densities of 2–3× 10²² cm⁻². Assuming standard X-factor values and that most of the HI/CO emission seen towards HESS J1731 − 347 is on the near-side of the Galaxy, X-ray absorption column densities are consistent with HI+CO-derived column densities foreground to, but not beyond, the Scutum–Crux Galactic arm, suggesting a kinematic distance of ∼3.2 kpc for HESS J1731 − 347. At this kinematic distance, we also find dense, infrared-dark gas traced by CS(1–0) emission coincident with the north of HESS J1731 − 347, the nearby HII region G353.43−0.37 and the nearby unidentified gamma-ray source HESS J1729 − 345. This dense gas lends weight to the idea that HESS J1729 − 345 and HESS J1731 − 347 are connected, perhaps via escaping cosmic-rays.N. Maxted, M. Burton, C. Braiding, G. Rowell, H. Sano, F. Voisin, M. Capasso, G. Pühlhofer and Y. Fuku
Erratum to: Effect of moderate red wine intake on cardiac prognosis after recent acute myocardial infarction of subjects with Type 2 diabetes mellitus (Diabetic Medicine, (2006), 23, 9, (974-981), 10.1111/j.1464-5491.2006.01886.x)
No full textIn an article by Marfella et al, the author name C. Saron is incorrect and should be listed as C. Sardu. Therefore the correct author list is: R. Marfella, F. Cacciapuoti, M. Siniscalchi, F. C. Sasso, F. Marchese, F. Cinone, E. Musacchio, M. A. Marfella, L. Ruggiero, G. Chiorazzo, D. Liberti, G. Chiorazzo, G. F. Nicoletti, C. Sardu, F. D'Andrea, C. Ammendola, M. Verza and L. Coppola.In an article by Marfella et al, the author name C. Saron is incorrect and should be listed as C. Sardu. Therefore the correct author list is: R. Marfella, F. Cacciapuoti, M. Siniscalchi, F. C. Sasso, F. Marchese, F. Cinone, E. Musacchio, M. A. Marfella, L. Ruggiero, G. Chiorazzo, D. Liberti, G. Chiorazzo, G. F. Nicoletti, C. Sardu, F. D'Andrea, C. Ammendola, M. Verza and L. Coppola
¿Qué hacen los mejores profesores de derecho? de Michael Hunter Schwartz, Gerry F. Hess y Sophie M. Sparrow
No full textFil: Iud, Alan. Universidad de Buenos Aires. Facultad de Derecho. Cátedra Régimen del Proceso Penal. Buenos Aires, ArgentinaSección Reseña. -- ¿Que hacen los mejores profesores de derecho? de Michael Hunter Schwartz, Gerry F. Hess y Sophie M. Sparrow. Ed. Universidad de Palermo, Buenos Aires, 2018. Título original: What the Best Law Teachers Do, Harvard University Press, 2013
Interstellar gas towards the TeV gamma-ray sources HESS J1640-465 and HESS J1641-463
No full textWe present a detailed analysis of the interstellar medium towards the tera electron volt (TeV) γ-ray sources HESS J1640−465 and HESS J1641−463 using results from the Mopra Southern Galactic Plane CO Survey and from a Mopra 7 mm-wavelength study. The γ-ray sources are positionally coincident with two supernova remnants (SNRs) G338.3−0.0 and G338.5+0.1, respectively. A bright complex of H ii regions connect the two SNRs and TeV objects. Observations in the CO(1–0) transition lines reveal substantial amounts of diffuse gas positionally coincident with the γ-ray sources at multiple velocities along the line of sight, while 7 mm observations in CS, SiO, HC3N and CH3OH transition lines reveal regions of dense, shocked gas. Archival H i data from the Southern Galactic Plane Survey was used to account for the diffuse atomic gas. Physical parameters of the gas towards the TeV sources were calculated from the data. We find that for a hadronic origin for the γ-ray emission, the cosmic ray enhancement rates are ∼103 and 102 times the local solar value for HESS J1640−465 and HESS J1641−463, respectively.J. C. Lau, G. Rowell, M. G. Burton, Y. Fukui, F. A. Aharonian, I. Oya, J. Vink, S. Ohm and S. Casanov
[Memo from Lieutenant Colonel M. F. Hass, Civil Affairs Division, with amendments to an evacuation proposal]
No full textA memorandum sent form Lieutenant General M. F. Hass, Civil Affairs Division, which has two corrections from a an evacuation proposal originally sent on May 13, 1942. The correction changes the destination to the Merced Assembly Center.The War Relocation Authority (WRA), together with the Wartime Civil Control Administration (WCCA), the Civil Affairs Division (CAD) and the Office of the Commanding General (OFG) of the Western Defense Command (WDC) operated together to segregate and house some 110,000 men women and children from 1942 to 1945. The collection contains documents and photographs relating to the establishment and administrative workings of the (WDC), the (WRA) and the (WCCA) for the year 1942
X-HESS: a large sample of highly accreting serendipitous AGN under the XMM-Newton microscope
No full textThe bulk of X-ray spectroscopic studies of active galactic nuclei (AGN) are
focused on local (z < 0.1) sources with low-to-moderate (< 0.3) Eddington
ratio (). It is then mandatory to overcome this
limitation and improve our understanding of highly accreting AGN. In this work
we present the preliminary results from the analysis of a sample of
high- radio-quiet AGN at , based on
the 10th release of the XMM-Newton serendipitous source catalogue, that we
named as XMM-Newton High-Eddington Serendipitous AGN Sample (X-HESS). Almost
of the X-HESS AGN have multi-epoch archival observations and
of the sources can rely on simultaneous OM optical data. First
results reveal sources showing signatures of ultra-fast outflows and remarkable
long- and short-term X-ray flux variations. Indeed in J095847.88+690532.7 (), one of the most densely monitored objects hosting a
supermassive black hole, we discovered a variation of the
soft X-ray flux by a factor of > 2 over approximately one week (rest-frame).
Large variations in the power-law continuum photon index are also
observed, questioning expectations from previously reported relations, for which would be a
ubiquitous hallmark of AGN with
On the binary nature of the γ-ray sources AGL J2241+4454 (= MWC 656) and HESS J0632+057 (= MWC 148)
No full textWe present optical spectroscopy of MWC 656 and MWC 148, the proposed optical counterparts of the gamma-ray sources AGL J2241+4454 and HESS J0632+0 57, respectively. The main parameters of the Halpha emission line (EW, FWHM and centroid velocity) in these stars are modulated on the proposed orbital periods of 60.37 and 321 days, respectively. These modulations are likely produced by the resonant interaction of the Be discs with compact stars in eccentric orbits. We also present radial velocity curves of the optical stars folded on the above periods and obtain the first orbital elements of the two gamma-ray sources thus confirming their binary nature. Our orbital solution support eccentricities e~0.4 and 0.83+-0.08 for MWC 656 and MWC 148, respectively. Further, our orbital elements imply that the X-ray outbursts in HESS J0632+057/MWC 148 are delayed ~0.3 orbital phases after periastron passage, similarly to the case of LS I +61 303. In addition, the optical photometric light curve maxima in AGL J2241+4454/MWC 656 occur ~0.25 phases passed periastron, similar to what is seen in LS I +61 303. We also find that the orbital eccentricity is correlated with orbital period for the known gamma-ray binaries. This is explained by the fact that small stellar separations are required for the efficient triggering of VHE radiation. Another correlation between the EW of Halpha and orbital period is also observed, similarly to the case of Be/X-ray binaries. These correlations are useful to provide estimates of the key orbital parameters Porb and e from the Halpha line in future Be gamma-ray binary candidates
A Study of the interstellar medium towards the unidentified dark TeV γ-Ray sources HESS J1614–518 and HESS J1616–508
No full textHESS J1614–518 and HESS J1616–508 are two tera-electron volt γ-ray sources that are not firmly associated with any known counterparts at other wavelengths. We investigate the distribution of interstellar medium towards the tera-electron volt γ-ray sources using results from a 7-mm-wavelength Mopra study, the Mopra Southern Galactic Plane CO Survey, the Millimetre Astronomer’s Legacy Team-45 GHz survey and [C i] data from the HEAT telescope. Data in the CO(1–0) transition lines reveal diffuse gas overlapping the two tera-electron volt sources at several velocities along the line of sight, while observations in the CS(1–0) transition line reveal several interesting dense gas features. To account for the diffuse atomic gas, archival H i data was taken from the Southern Galactic Plane Survey. The observations reveal gas components with masses ~103 to 105 M⊙ and with densities ~102 to 103 cm−3 overlapping the two tera-electron volt sources. Several origin scenarios potentially associated with the tera-electron volt γ-ray sources are discussed in light of the distribution of the local interstellar medium. We find no strong convincing evidence linking any counterpart with HESS J1614–518 or HESS J1616–508.J. C. Lau, G. Rowell, F. Voisin, C. Braiding, M. Burton, Y. Fukui, S. Pointon, M. Ashley, C. Jordan and A. Wals
HESS - The High Energy Stereoscopic System
No full textProceedings edition under the auspices of the International Union of Pure and Applied Physics (IUPAP)The HESS collaboration is planning to build a large Imaging Atmospheric Cherenkov Telescope (IACT) arrayin the Southern Hemisphere in the Khomas Highland of Namibia. In its final stage, the HESS experiment willhave up to 16 telescopes each with a 80 m reflector and a high resolution camera. The schedule foresees tostart with scientific operation of the first 4-telescope subsystem in 2002 (Phase 1).HESS will have a detection threshold of about 40 GeV and an angular resolution of less than a few arcmin-utes. The flux sensitivity above 100 GeV of 1
HESS - The High Energy Stereoscopic System
No full textProceedings edition under the auspices of the International Union of Pure and Applied Physics (IUPAP)The HESS collaboration is planning to build a large Imaging Atmospheric Cherenkov Telescope (IACT) arrayin the Southern Hemisphere in the Khomas Highland of Namibia. In its final stage, the HESS experiment willhave up to 16 telescopes each with a 80 m reflector and a high resolution camera. The schedule foresees tostart with scientific operation of the first 4-telescope subsystem in 2002 (Phase 1).HESS will have a detection threshold of about 40 GeV and an angular resolution of less than a few arcmin-utes. The flux sensitivity above 100 GeV of 1
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