Probing extra spacetime dimensions at the Tevatron

Theories with extra spacetime dimensions aiming at resolving the hierarchy problem have recently been developed. These scenarios have provided exciting new grounds for experimental probes. A review of the searches conducted at the Tevatron in this framework during its first running phase and the prospects for its second running phase are reviewed.Comment: Proceedings of the SUSY 2002 conference, Hamburg, Germany. 8 pages corrected reference and a typ

Bavay – Cité d’Angoulème, terrain Mandron-Peyron

Date de l'opération : 1991 (SU) ; 1991 (SD) Inventeur(s) : Loridant Frédéric ; Duflot Laurent Le terrain Mandron-Peyron [ (Fig. n°1 : Localisation des zones fouillées), site C] est situé au nord-ouest de la ville, à proximité du forum, entre les voies antiques Bavay-Tournai (actuellement, RN49) et Bavay-Blicquy (idem, CD24). L’importante superficie (2 ha) laissée à l’investigation archéologique donne l’occasion unique de mieux connaître l’habitat gallo-romain et surtout de préciser l’ancienn..

Moulézan – Carrière Héral-Nègre

Date de l'opération : 1993 - 1995 (SP) Inventeur(s) : Bessac Jean-Claude (CNRS) ; Duflo Laurent La carrière Héral-Nègre est actuellement exploitée par la société Rocamat à l'extrémité orientale de la commune de Moulézan (Gard). Elle est ouverte dans un sous-faciès oolithique de l'affleurement de calcaire urgonien du Bois des Lens [(Bessac, Jean-Claude ; Blanc, Annie ; Blanc, Philippe. 1990.), p. 406, planche I ; (Bessac, Jean-Claude ; Aucher, Marie-Reine ; Blanc, Annie ; Blanc, Philippe. 1996..

Nîmes – Îlot Grill

Date de l'opération : 1992 (SD) ; 1993 (SU) Inventeur(s) : Hervé Marie-Laure (AFAN) ; Duflot Laurence Plan général des opérations intra muros de Nîmes (Fig. n°3 : En noir, les principales fouilles réalisées entre 1965 et 1990 à l’intérieur de la ville du Haut-Empire, associées à quelques grands repères topographiques). À l’angle formé par le boulevard des Arènes, la rue de la République et la rue Alexandre-Ducros (EZ-474, 475), un projet immobilier devait concerner des parcelles situées sur ..

Water ice deuteration: a tracer of the chemical history of protostars

Context. Millimetric observations have measured high degrees of molecular deuteration in several species seen around low-mass protostars. The Herschel Space Telescope, launched in 2009, is now providing new measures of the deuterium fractionation of water, the main constituent of interstellar ices. Aims. We aim at theoretically studying the formation and the deuteration of water, which is believed to be formed on interstellar grain surfaces in molecular clouds. Methods. We used our gas-grain astrochemical model GRAINOBLE, which considers the multilayer formation of interstellar ices. We varied several input parameters to study their impact on water deuteration. We included the treatment of ortho- and para-states of key species, including H2, which affects the deuterium fractionation of all molecules. The model also includes relevant laboratory and theoretical works on the water formation and deuteration on grain surfaces. In particular, we computed the transmission probabilities of surface reactions using the Eckart model, and we considered ice photodissociation following molecular dynamics simulations. Results. The use of a multilayer approach allowed us to study the influence of various parameters on the abundance and the deuteration of water. Deuteration of water is found to be very sensitive to the ortho-to-para ratio of H2 and to the total density, but it also depends on the gas/grain temperatures and the visual extinction of the cloud. Since the deuteration is very sensitive to the physical conditions, the comparison with sub-millimetric observation towards the low-mass protostar IRAS 16293 allows us to suggest that water ice is formed together with CO2 in molecular clouds with limited density, whilst formaldehyde and methanol are mainly formed in a later phase, where the condensation becomes denser and colder.Comment: Accepted for publication to A&A. 24 pages, 10 figure

MSSM-inflation revisited: Towards a coherent description of high-energy physics and cosmology

The aim of this paper is to highlight the challenges and potential gains surrounding a coherent description of physics from the high-energy scales of inflation down to the lower energy scales probed in particle-physics experiments. As an example, we revisit the way inflation can be realised within an effective Minimal Supersymmetric Standard Model (eMSSM), in which the $LLe$ and $udd$ flat directions are lifted by the combined effect of soft-supersymmetric-breaking masses already present in the MSSM, together with the addition of effective non-renormalizable operators. We clarify some features of the model and address the question of the one-loop Renormalization Group improvement of the inflationary potential, discussing its impact on the fine-tuning of the model. We also compare the parameter space that is compatible with current observations (in particular the amplitude, $A_{\scriptscriptstyle{\mathrm{S}}}$, and the spectral index, $n_{\scriptscriptstyle{\mathrm{S}}}$, of the primordial cosmological fluctuations) at tree level and at one loop, and discuss the role of reheating. Finally we perform combined fits of particle and cosmological observables (mainly $A_{\scriptscriptstyle{\mathrm{S}}}$, $n_{\scriptscriptstyle{\mathrm{S}}}$, the Higgs mass, and the cold-dark-matter energy density) with the one-loop inflationary potential applied to some examples of dark-matter annihilation channels (Higgs-funnel, Higgsinos and A-funnel), and discuss the status of the ensuing MSSM spectra with respect to the LHC searches.Comment: 38 pages, 7 figure

Probabilistic Model Checking of the CSMA/CD Protocol Using PRISM and APMC

AbstractCarrier Sense Multiple Access/Collision Detection (CSMA/CD) is the protocol for carrier transmission access in Ethernet networks (international standard IEEE 802.3). On Ethernet, any Network Interface Card (NIC) can try to send a packet in a channel at any time. If another NIC tries to send a packet at the same time, a collision is said to occur and the packets are discarded. The CSMA/CD protocol was designed to avoid this problem, more precisely to allow a NIC to send its packet without collision. This is done by way of a randomized exponential backoff process. In this paper, we analyse the correctness of the CSMA/CD protocol, using techniques from probabilistic model checking and approximate probabilistic model checking. The tools that we use are PRISM and APMC. Moreover, we provide a quantitative analysis of some CSMA/CD properties

ISO observations of the interacting galaxy Markarian 297: with the powerful supernova remnant 1982aa

Markarian (Mkn) 297 is a complex system with two interacting galaxies. Observations were made with ISO using ISOCAM, ISOPHOT and LWS. We present ISOCAM maps at 6.7, 7.7, 12 and 14.3 microns which, with PHT-S spectrometry of the central interacting region, probe the dust obscured star formation and dust properties. ISOCAM reveals that the strongest emission region in the four MIR bands is completely unremarkable at visible and near-IR (e.g. 2MASS) wavelengths, and does not coincide with the nuclear region of either colliding galaxy. It shares this striking characteristic with the overlap region of the colliding galaxies in the Antennae (NGC 4038, 4039), the intragroup region of Stephan's Quintet, and IC 694 in the interacting system Arp 299. At 15 microns, the hidden source in Mkn 297 is, respectively, 14.6 and 3.8 times more luminous than the hidden sources in the Antennae (NGC 4038/4039) and Stephan's Quintet. Numerical simulations indicate that we see the Mkn 297 interaction about 1.5 x 10e8 years after the collision. ISOCAM shows knots and ridges of emission. The 14.3/7.7 micron ratio map implies widespread strong star formation. Strong emission features were detected in the ISOPHOT spectrum, while [OI], [OIII] and [CII] emission lines were seen with LWS. Using data from the three instruments, luminosities and masses for two dust components were determined. The total infrared luminosity is approximately 10e11 L_sol, marginally a LIRG. A 1979 supernova generated one of the most powerful known radio remnants (SN 1982aa) close to the strongest MIR source and identified with star forming region 14 in the optical. This exceptional supernova explosion may have been accompanied by a GRB, and a search for a GRB in this direction in contemporaneous satellite data is recommended.Comment: Accepted for publication in Astronomy and Astrophysics Updated to better use recent SN/GRB work and tune terminology in Sec. 4.