Distributed analysis with CRAB: The client-server architecture evolution and commissioning

CRAB (CMS Remote Analysis Builder) is the tool used by CMS to enable running physics analysis in a transparent manner over data distributed across many sites. It abstracts out the interaction with the underlying batch farms, grid infrastructure and CMS workload management tools, such that it is easily usable by non-experts. CRAB can be used as a direct interface to the computing system or can delegate the user task to a server. Major efforts have been dedicated to the client-server system development, allowing the user to deal only with a simple and intuitive interface and to delegate all the work to a server. The server takes care of handling the users jobs during the whole lifetime of the users task. In particular, it takes care of the data and resources discovery, process tracking and output handling. It also provides services such as automatic resubmission in case of failures, notification to the user of the task status, and automatic blacklisting of sites showing evident problems beyond what is provided by existing grid infrastructure. The CRAB Server architecture and its deployment will be presented, as well as the current status and future development. In addition the experience in using the system for initial detector commissioning activities and data analysis will be summarized

Observation of the TeV gamma-ray source MGRO J1908+06 with ARGO-YBJ

The extended gamma ray source MGRO J1908+06, discovered by the Milagro air shower detector in 2007, has been observed for about 4 years by the ARGO-YBJ experiment at TeV energies, with a statistical significance of 6.2 standard deviations. The peak of the signal is found at a position consistent with the pulsar PSR J1907+0602. Parametrizing the source shape with a two-dimensional Gauss function we estimate an extension \sigma = 0.49 \pm 0.22 degrees, consistent with a previous measurement by the Cherenkov Array H.E.S.S.. The observed energy spectrum is dN/dE = 6.1 \pm 1.4 \times 10^-13 (E/4 TeV)^{-2.54 \pm 0.36} photons cm^-2 s^-1 TeV^-1, in the energy range 1-20 TeV. The measured gamma ray flux is consistent with the results of the Milagro detector, but is 2-3 times larger than the flux previously derived by H.E.S.S. at energies of a few TeV. The continuity of the Milagro and ARGO-YBJ observations and the stable excess rate observed by ARGO-YBJ along 4 years of data taking support the identification of MGRO J1908+06 as the steady powerful TeV pulsar wind nebula of PSR J1907+0602, with an integrated luminosity above 1 TeV about 1.8 times the Crab Nebula luminosity.Comment: 6 pages, accepted for pubblication by ApJ. Replaced to correct the author lis

Long-term Monitoring on Mrk 501 for Its VHE gamma Emission and a Flare in October 2011

As one of the brightest active blazars in both X-ray and very high energy $\gamma$-ray bands, Mrk 501 is very useful for physics associated with jets from AGNs. The ARGO-YBJ experiment is monitoring it for $\gamma$-rays above 0.3 TeV since November 2007. Starting from October 2011 the largest flare since 2005 is observed, which lasts to about April 2012. In this paper, a detailed analysis is reported. During the brightest $\gamma$-rays flaring episodes from October 17 to November 22, 2011, an excess of the event rate over 6 $\sigma$ is detected by ARGO-YBJ in the direction of Mrk 501, corresponding to an increase of the $\gamma$-ray flux above 1 TeV by a factor of 6.6$\pm$2.2 from its steady emission. In particular, the $\gamma$-ray flux above 8 TeV is detected with a significance better than 4 $\sigma$. Based on time-dependent synchrotron self-Compton (SSC) processes, the broad-band energy spectrum is interpreted as the emission from an electron energy distribution parameterized with a single power-law function with an exponential cutoff at its high energy end. The average spectral energy distribution for the steady emission is well described by this simple one-zone SSC model. However, the detection of $\gamma$-rays above 8 TeV during the flare challenges this model due to the hardness of the spectra. Correlations between X-rays and $\gamma$-rays are also investigated.Comment: have been accepted for publication at Ap

ISTITUTO NAZIONALE DI FISICA NUCLEARE GLUE SCHEMA IMPLEMENTATION FOR THE LDAP DATA MODEL *

Abstract An important aspect of the interoperability among different Grid systems is the definition of a common schema for the representation of Grid resources. This is vital for sharing the status and availability of resources at the virtual level. The GLUE schema is designed to fulfil this need by providing a conceptual schema of the relevant resources. This paper presents a mapping of this schema into the LDAP data model. It is used in the Globus MDS version 2. Published by SIS-Pubblicazioni Laboratori Nazionali di Frascat

VOMS/VOMRS utilization patterns and convergence plan

The Grid community uses two well-established registration services, which allow users to be authenticated under the auspices of Virtual Organizations (VOs). The Virtual Organization Membership Service (VOMS), developed in the context of the Enabling Grid for E-sciencE (EGEE) project, is an Attribute Authority service that issues attributes expressing membership information of a subject within a VO. VOMS allows to partition users in groups, assign them roles and free-form attributes which are then used to drive authorization decisions. The VOMS administrative application, VOMS-Admin, manages and populates the VOMS database with membership information. The Virtual Organization Management Registration Service (VOMRS), developed at Fermilab, extends the basic registration and management functionalities present in VOMS-Admin. It implements a registration workflow that requires VO usage policy acceptance and membership approval by administrators. VOMRS supports management of multiple grid certificates, and handling users' request for group and role assignments, and membership status. VOMRS is capable of interfacing to local systems with personnel information (e.g. the CERN Human Resource Database) and of pulling relevant member information from them. VOMRS synchronizes the relevant subset of information with VOMS. The recent development of new features in VOMS-Admin raises the possibility of rationalizing the support and converging on a single solution by continuing and extending existing collaborations between EGEE and OSG. Such strategy is supported by WLCG, OSG, US CMS, US Atlas, and other stakeholders worldwide. In this paper, we will analyze features in use by major experiments and the use cases for registration addressed by the mature single solution

Top cross section measurement at CDF

This paper describes the latest measurements of the t{bar t} pair production cross section performed by the CDF Collaboration analyzing p{bar p} collisions at a center-of-mass energy of 1.96 TeV from Fermilab Tevatron, as presented at the XVIII International Workshop on Deep-Inelastic Scattering and Related Subjects. In order to test Standard Model predictions, several analysis methods are explored and all the top decay channels are considered, to better constrain the properties of the top quark and to search for possible sources of new physics affecting the pair production mechanism. Experimental results using an integrated luminosity up to 5.1 fb{sup -1} are presented

Familles, migrations et solidarités intergénérationnelles : enjeux politiques et sociétaux

La globalisation et l’accélération des flux migratoires conduisent un nombre grandissant de personnes à vivre leurs relations familiales par-delà les frontières géographiques, dans un contexte de démocratisation relative des transports et d’un accès accru à des technologies de la communication de plus en plus sophistiquées. Cette présentation s’appuie sur un programme de recherche (TRANSFAM) qui s’inscrit dans le champ d’étude des familles dites ‘transnationales’, qui comptent en leur sein des membres vivant dans différents pays et qui maintiennent vivants leurs liens familiaux, notamment via des pratiques d’entraide familiale désormais transnationales. De nos jours, les migrants échangent à des degrés divers du soutien matériel, financier, pratique et émotionnel avec leurs enfants, leurs frères et sœurs, et leurs parents vieillissants, parfois quotidiennement. Ces différents protagonistes se déplacent également pour prendre soin de, ou être pris en charge par les leurs. Articuler vie familiale et professionnelle dans un tel contexte pose de réels défis. Cette présentation passera notamment en revue les ressources dont ces familles ont besoin pour participer à ces solidarités, et identifiera les politiques qui facilitent, ou au contraire font obstacle au maintien de ces solidarités

Top cross section measurement at CDF

This paper describes the latest measurements of the t{bar t} pair production cross section performed by the CDF Collaboration analyzing p{bar p} collisions at a center-of-mass energy of 1.96 TeV from Fermilab Tevatron, as presented at the XVIII International Workshop on Deep-Inelastic Scattering and Related Subjects. In order to test Standard Model predictions, several analysis methods are explored and all the top decay channels are considered, to better constrain the properties of the top quark and to search for possible sources of new physics affecting the pair production mechanism. Experimental results using an integrated luminosity up to 5.1 fb{sup -1} are presented