Excitation and Disruption of a Giant Molecular Cloud by the Supernova Remnant 3C391

Using the IRAM 30-m telescope, we observed the supernova remnant 3C 391 (G31.9+0.0) and its surroundings in the CO(2-1), HCO+(1-0), CS(2-1), CS(3-2), and CS(5-4) lines. The ambient molecular gas at the distance (9 kpc) of the remnant comprises a giant molecular cloud whose edge is closely parallel to a ridge of bright non-thermal radio continuum, which evidently delineates the blast-wave into the cloud. We found that in a small (0.6 pc) portion of the radio shell, the molecular line profiles consist of a narrow (2 km/s) component, plus a very wide (> 20 km/s) component. Both spectral components peak within 20" of a previously-detected OH 1720 MHz maser. We name this source 3C 391:BML (broad molecular line); it provides a new laboratory, similar to IC 443 but on a larger scale, to study shock interactions with dense molecular gas. The wide spectral component is relatively brighter in the higher-excitation lines. We interpret the wide spectral component as post-shock gas, either smoothly accelerated or partially dissociated and reformed behind the shock. The narrow component is either the pre-shock gas or cold gas reformed behind a fully dissociative shock. Using the 3 observed CS lines, we measured the temperature, CS column density, and H2 volume density in a dense clump in the parent molecular cloud as well as the wide-line and narrow-line portions of the shocked clump. The physical conditions of the narrow-line gas are comparable to the highest-density clumps in the giant molecular cloud, while the wide-line gas is both warmer and denser. The mass of compressed gas in 3C 391:BML is high enough that its self-gravity is significant, and eventually it could form one or several stars

Erratum: Corrigendum: Sequence and comparative analysis of the chicken genome provide unique perspectives on vertebrate evolution

International Chicken Genome Sequencing Consortium. The Original Article was published on 09 December 2004. Nature432, 695–716 (2004). In Table 5 of this Article, the last four values listed in the ‘Copy number’ column were incorrect. These should be: LTR elements, 30,000; DNA transposons, 20,000; simple repeats, 140,000; and satellites, 4,000. These errors do not affect any of the conclusions in our paper. Additional information. The online version of the original article can be found at 10.1038/nature0315

SHARK-NIR, first results of the commissioning at LBT

International audienceSHARK-NIR, first results of the commissioning at LB

SHARK-NIR, first results of the commissioning at LBT

International audienceSHARK-NIR, first results of the commissioning at LB

SHARK-NIR, first results of the commissioning at LBT

SHARK-NIR is an instrument which provides direct imaging, both coronagraphic and non-coronagraphic and with the possibility to perform dual-band imaging and low-resolution spectroscopy in Y, J and H bands, with the main scientific goal of detecting exoplanets, and characterizing already known planets, young stellar systems, jets and disks. SHARK-NIR takes advantage of the excellent performance of the Large Binocular Telescope AO systems, the wavefront sensors of which have been recently upgraded to SOUL. The latter is delivering a very good performance also at faint magnitude, opening to science otherwise difficult to be achieved, as for example AGN and QSO morphological studies. To fully exploit the just mentioned science cases, binocular observations will be performed using SHARK-NIR in combination with SHARK-VIS (operating in B, V, R and I bands) and LMIRCam of LBTI (operating from K to M bands), in a way to exploit coronagraphic observations in three different wavelengths. The instrument has passed the preliminary acceptance Europe in March 2022, being shipped immediately after at LBT, and re-integrated, installed and characterized daytime in three pre-commissioning run at the telescoped. SHARK-NIR had a very successful first light in January this year, and we will report of the results obtained in the three commissioning runs performed in the first half of 2023

Sequence and comparative analysis of the chicken genome provide unique perspectives on vertebrate evolution

We present here a draft genome sequence of the red jungle fowl, Gallus gallus. Because the chicken is a modern descendant of the dinosaurs and the first non-mammalian amniote to have its genome sequenced, the draft sequence of its genome--composed of approximately one billion base pairs of sequence and an estimated 20,000-23,000 genes--provides a new perspective on vertebrate genome evolution, while also improving the annotation of mammalian genomes. For example, the evolutionary distance between chicken and human provides high specificity in detecting functional elements, both non-coding and coding. Notably, many conserved non-coding sequences are far from genes and cannot be assigned to defined functional classes. In coding regions the evolutionary dynamics of protein domains and orthologous groups illustrate processes that distinguish the lineages leading to birds and mammals. The distinctive properties of avian microchromosomes, together with the inferred patterns of conserved synteny, provide additional insights into vertebrate chromosome architecture