Short and medium term variability study of NGC2516 solar type stars with EPIC

Assessment of contamination of Salmonella spp. in imported black pepper and sesame seed and salmonella inactivation by gamma irradiation

This study shows the frequency of seeds samples contaminated by Salmonella spp. collected randomly from local markets; on 30 black pepper sample no contaminated sample was found while Salmonella spp. was detected in 3 of 36 (8.3%) analyzed sesame samples; three different serotypes were identified: S. Montevideo, S. Stanleyville e S. Tilene. The efficacy of gamma irradiation to inactivate Salmonella Montevideo in black pepper and sesame irradiated between 1 and 5 kGy was evaluated. 3 kGy is sufficient to reduce of 3-4 log CFU/g; whereas 5 kGy have been need to reduce 5.5-6 log CFU/g for samples of black pepper and sesame. No statistically significant differences were found between black pepp…

Photometry of candidate members of NGC6611

We present the list of candidate members of the young open cluster NGC 6611, selected in a field of view of 33'x34' by the X-rays emission and excesses in infrared bands. X-ray sources without infrared excesses are classified as candidate Class III cluster members; stars with infrared excesses as disk bearing members. Cone search capability for table J/A+A/496/453/catalog (NGC 6611 cluster member positions and magnitudes)

XMM sources in Blanco 1

We present an X-ray study of the high metallicity young open cluster Blanco 1 based on XMM-Newton data. X-ray spectroscopy of cluster members is presented for the first time as well as new X-ray distribution functions of late-type stars. We detected all known dF and dG stars in the EPIC field and 80% and 90% of dK and dM stars, respectively. The X-ray spectral analysis of the X-ray brightest cluster stars and X-ray color analysis of a larger sample show that a model with two temperatures (at about 0.3 and 1keV) explains the quiescent activity phase spectra. We discuss also the nature of unidentified X-ray sources in the observed region and their X-ray spectral properties. Cone search capabi…

Chandra X-ray sources in Orion Nebula Cluster

In this first of two companion papers on the Orion Nebula Cluster (ONC), we present our analysis of a 63ks Chandra HRC-I observation that yielded 742 X-ray detections within the 30'x30' field of view. To facilitate our interpretation of the X-ray image, here we collect a multiwavelength catalog of nearly 2900 known objects in the region by combining 17 different catalogs from the recent literature. We define two reference groups: an infrared sample, containing all objects detected in the K band, and an optical sample comprising low-extinction, well-characterized ONC members. We show for both samples that field object contamination is generally low. Our X-ray sources are primarily low-mass O…

X-ray Luminosities in Blanco 1

We present X-ray Luminosity Distributions (XLDs) of late-type members (dF, dG, dK, dM) of the Blanco 1 cluster, based on ROSAT-HRI data and new astrometric-photometric membership obtained from the GSC-II project. For the first time we present the XLD of dM stars of this cluster. The high metallicity of Blanco 1 allows us to investigate the role of chemical composition on the coronal emission of late-type stars. Comparison between X-ray Luminosity Distributions of Blanco 1 and Pleiades, NGC 2516 and {alpha} Per suggests a possible metallicity effect in dM stars. Cone search capability for table J/A+A/399/919/tablea1 (Optical, infrared and X-ray band properties of Blanco 1 members in the comb…

XMM observations of IC 2391 stars

We present X-ray spectral and timing analysis of members of the young open cluster IC 2391 observed with the XMM-Newton observatory. We detected 99 X-ray sources by analysing the summed data obtained from MOS1, MOS2 and pn detectors of the EPIC camera; 24 of them are members, or probable members, of the cluster. Stars of all spectral types have been detected, from the early-types to the late-M dwarfs. Cone search capability for table J/A+A/430/287/table1 (XMM-Newton sources in the IC 2391 region, as detected in the combined EPIC image.) Cone search capability for table J/A+A/430/287/table2 (X-ray and optical properties of IC 2391 members, and upper limits in the combined EPIC image.)

Blue stars with disk photometry in NGC 6611

NGC 6611 and its parental cloud, the Eagle Nebula (M 16), are well-studied star-forming regions, thanks to their large content of both OB stars and stars with disks and the observed ongoing star formation. In our previous studies of the Eagle Nebula, we identified 834 disk-bearing stars associated with the cloud, after detecting their excesses in NIR bands from J band to 8.0um. In this paper, we study in detail the nature of a subsample of disk-bearing stars that show peculiar characteristics. They appear older than the other members in the V vs. V-I diagram, and/or they have one or more IRAC colors at pure photospheric values, despite showing NIR excesses, when optical and infrared colors …

UBVRI photometry of NGC 2422

We present UBVRI photometry of the open cluster NGC 2422 (age~10^8^yr) down to a limiting magnitude V=~19. These data are used to derive the Luminosity and Mass Functions and to study the cluster spatial distribution. By considering the color-magnitude diagram data and adopting a representative cluster main sequence, we obtained a list of candidate cluster members based on a photometric criterion. Cone search capability for table J/A+A/404/927/table4 (Astrometric/photometric catalog of candidate members of the open cluster NGC 2422)