A. Punanova

The MASTER-II network of robotic optical telescopes. First results

The main stages in the creation of the Russian segment of the MASTER network of robotic telescopes is described. This network is designed for studies of the prompt optical emission of gammaray bursts (GRBs; optical emission synchronous with the gamma-ray radiation) and surveys of the sky aimed at discovering uncataloged objects and photometric studies for various programs. The first results obtained by the network, during its construction and immediately after its completion in December 2010, are presented. Eighty-nine alert pointings at GRBs (in most cases, being the first ground telescopes to point at the GRBs) were made from September 2006 through July 2011. The MASTER network holds first place in the world in terms of the total number of first pointings, and currently more than half of first pointings at GRBs by ground telescopes are made by the MASTER network. Photometric light curves of GRB 091020, GRB 091127, GRB 100901A, GRB 100906A, GRB 10925A, GRB 110106A, GRB 110422A, and GRB 110530A are presented. It is especially important that prompt emission was observed for GRB 100901A and GRB 100906A, and thar GRB 091127, GRB 110422A, and GRB 110106A were observed from the first seconds in two polarizations. Very-wide-field cameras carried out synchronous observations of the prompt emission of GRB 081102, GRB 081130B, GRB 090305B, GRB 090320B, GRB 090328, and GRB 090424. Discoveries of Type Ia supernovae are ongoing (among them the brightest supernova in 2009): 2008gy, 2009nr, 2010V, and others. In all, photometry of 387 supernovae has been carried out, 43 of which were either discovered or first observed with MASTER telescopes; more than half of these are Type Ia supernovae. Photometric studies of the open clusters NGC 7129 and NGC 7142 have been conducted, leading to the discovery of 38 variable stars. Sixty-nine optical transients have been discovered.

The Green Bank Ammonia Survey: First Results of NH3 Mapping of the Gould Belt

We present an overview of the first data release (DR1) and first-look science from the Green Bank Ammonia Survey (GAS). GAS is a Large Program at the Green Bank Telescope to map all Gould Belt star-forming regions with AV & 7 mag visible from the northern hemisphere in emission from NH3 and other key molecular tracers. This first release includes the data for four regions in Gould Belt clouds: B18 in Taurus, NGC 1333 in Perseus, L1688 in Ophiuchus, and Orion A North in Orion. We compare the NH3 emission to dust continuum emission from Herschel, and find that the two tracers correspond closely. NH3 is present in over 60 % of lines-of-sight with AV & 7 mag in three of the four DR1 regions, in agreement with expectations from previous observations. The sole exception is B18, where NH3 is detected toward ∼ 40 % of lines-of-sight with AV & 7 mag. Moreover, we find that the NH3 emission is generally extended beyond the typical 0.1 pc length scales of dense cores. We produce maps of the gas kinematics, temperature, and NH3 column densities through forward modeling of the hyperfine structure of the NH3 (1,1) and (2,2) lines. We show that the NH3 velocity dispersion, σv, and gas kinetic temperature, TK, vary systematically between the regions included in this release, with an increase in both the mean value and spread of σv and TK with increasing star formation activity. The data presented in this paper are publicly available.

Deuterium fractionation in the Ophiuchus molecular cloud

Aims. We measure the deuterium fraction, RD, and the CO-depletion factor, fd, toward a number of starless and protostellar cores in the L1688 region of the Ophiuchus molecular cloud complex and search for variations based upon environmental differences across L1688. The kinematic properties of the dense gas traced by the N2H+ and N2D+ (1-0) lines are also discussed. Methods. RD has been measured via observations of the J=1-0 transition of N2H+ and N2D+ toward 33 dense cores in different regions of L1688. fd estimates have been done using C17O(1-0) and 850 micron dust continuum emission from the SCUBA survey. All line observations were carried out with the IRAM 30 meter antenna. Results. The dense cores show large (2-40%) deuterium fractions, with significant variations between the sub-regions of L1688. The CO-depletion factor also varies from one region to another (1-7). Two different correlations are found between deuterium fraction and CO-depletion factor: cores in regions A, B2 and I show increasing RD with increasing fd, similar to previous studies of deuterium fraction in pre-stellar cores; cores in regions B1, B1B2, C, E, F and H show a steeper RD-fd correlation, with large deuterium fractions occurring in fairly quiescent gas with relatively low CO freeze-out factors. These are probably recently formed, centrally concentrated starless cores which have not yet started the contraction phase toward protostellar formation. We also find that the deuterium fraction is affected by the amount of turbulence, dust temperature and distance from heating sources in all regions of L1688, although no clear trend is found.

Seeds of Life in Space (SOLIS) II. Formamide in protostellar shocks: Evidence for gas-phase formation

Context. Modern versions of the Miller-Urey experiment claim that formamide (NH 2 CHO) could be the starting point for the formation of metabolic and genetic macromolecules. Intriguingly, formamide is indeed observed in regions forming solar-type stars and in external galaxies. Aims. How NH 2 CHO is formed has been a puzzle for decades: our goal is to contribute to the hotly debated question of whether formamide is mostly formed via gas-phase or grain surface chemistry. Methods. We used the NOrthern Extended Millimeter Array (NOEMA) interferometer to image NH 2 CHO towards the L1157-B1 blue-shifted shock, a well-known interstellar laboratory, to study how the components of dust mantles and cores released into the gas phase triggers the formation of formamide. Results. We report the first spatially resolved image (size ~9″, ~2300 AU) of formamide emission in a shocked region around a Sun-like protostar: the line profiles are blueshifted and have a FWHM ≃ 5 km s -1 . A column density of N NH 2 CHO = 8 × 10 12 cm -1 and an abundance, with respect to H-nuclei, of 4 × 10 -9 are derived. We show a spatial segregation of formamide with respect to other organic species. Our observations, coupled with a chemical modelling analysis, indicate that the formamide observed in L1157-B1 is formed by a gas-phase chemical process and not on grain surfaces as previously suggested. Conclusions. The Seeds of Life in Space (SOLIS) interferometric observations of formamide provide direct evidence that this potentially crucial brick of life is efficiently formed in the gas phase around Sun-like protostars.

Upgrade of the fiber-fed spectrograph of the Kourovka Astronomical Observatory

We report the results of testing the high-resolution fiber-fed spectrograph of Kourovka Astronomical Observatory of the Ural Federal University in 2010–2012 and the corresponding operation experience, and demonstrate the need for an upgrade of the instrument. We also describe the modifications that were made to the design of the spectrograph during the start of its regular operation in 2010 and the refurbishment of its suspended part carried out in 2013, which allowed to expand the capabilities of the instrument.

Seeds Of Life In Space (SOLIS): The Organic Composition Diversity at 300–1000 au Scale in Solar-type Star-forming Regions*

Complex organic molecules have been observed for decades in the interstellar medium. Some of them might be considered as small bricks of the macromolecules at the base of terrestrial life. It is hence particularly important to understand organic chemistry in Solar-like star-forming regions. In this article, we present a new observational project: Seeds Of Life In Space (SOLIS). This is a Large Project using the IRAM-NOEMA interferometer, and its scope is to image the emission of several crucial organic molecules in a sample of Solar-like star-forming regions in different evolutionary stages and environments. Here we report the first SOLIS results, obtained from analyzing the spectra of different regions of the Class 0 source NGC 1333-IRAS4A, the protocluster OMC-2 FIR4, and the shock site L1157-B1. The different regions were identified based on the images of formamide (NH2CHO) and cyanodiacetylene (HC5N) lines. We discuss the observed large diversity in the molecular and organic content, both on large (3000–10,000 au) and relatively small (300–1000 au) scales. Finally, we derive upper limits to the methoxy fractional abundance in the three observed regions of the same order of magnitude of that measured in a few cold prestellar objects, namely ~10-12-10-11 with respect to H2 molecules.

Trajectory retrieval and component investigations of the southern polar stratosphere based on high-resolution spectroscopy of the totally eclipsed moon surface

Abstract In this paper we present the high-resolution spectral observations of the fragment of lunar surface during the total lunar eclipse of December 10, 2011. The observations were carried out with the fiber-fed echelle spectrograph at the 1.2-m telescope in Kourovka Astronomical observatory (Ural mountains, central Russia). The observed radiation is transmitted by tangent trajectory through the southern polar stratosphere before the reflection from the Moon and the spectra contain a number of absorption bands of atmospheric gases (O2, O3, O4, NO2, H2O). High-resolution analysis of three O2 bands and O4 absorption effects is used to trace the effective trajectory of solar emission through the stratosphere and to detect the contribution of scattered light. Bands of other gases allow us to measure their abundances along the trajectory.

Deuteration of ammonia in the starless core Ophiuchus/ H-MM1

Ammonia and its deuterated isotopologues probe physical conditions in dense molecular cloud cores. With the aim of testing the current understanding of the spin-state chemistry of these molecules, we observed spectral lines of NH3, NH2D, NHD2, ND3, and N2D+ towards a dense, starless core in Ophiuchus with the APEX, GBT, and IRAM 30-m telescopes. The observations were interpreted using a gas-grain chemistry model combined with radiative transfer calculations. The chemistry model distinguishes between the different nuclear spin states of light hydrogen molecules, ammonia, and their deuterated forms. High deuterium fractionation ratios with NH2D/NH3=0.4, NHD2/NH2D=0.2, and ND3/NHD2=0.06 were found in the core. The observed ortho/para ratios of NH2D and NHD2 are close to the corresponding nuclear spin statistical weights. The chemistry model can approximately reproduce the observed abundances, but predicts uniformly too low ortho/para-NH2D, and too large ortho/para-NHD2 ratios. The longevity of N2H+ and NH3 in dense gas, which is prerequisite to their strong deuteration, can be attributed to the chemical inertia of N2 on grain surfaces. The discrepancies between the chemistry model and the observations are likely to be caused by the fact that the model assumes complete scrambling in principal gas-phase deuteration reactions of ammonia, which means that all the nuclei are mixed in reactive collisions. If, instead, these reactions occur through proton hop/hydrogen abstraction processes, statistical spin ratios are to be expected. The present results suggest that while the deuteration of ammonia changes with physical conditions and time, the nuclear spin ratios of ammonia isotopologues do not probe the evolutionary stage of a cloud.

The Green Bank Ammonia Survey: Dense Cores under Pressure in Orion A

We use gas temperature and velocity dispersion data from the Green Bank Ammonia Survey and core masses and sizes from the James Clerk Maxwell Telescope Gould Belt Survey to estimate the virial states of dense cores within the Orion A molecular cloud. Surprisingly, we find that almost none of the dense cores are sufficiently massive to be bound when considering only the balance between self-gravity and the thermal and non-thermal motions present in the dense gas. Including the additional pressure binding imposed by the weight of the ambient molecular cloud material and additional smaller pressure terms, however, suggests that most of the dense cores are pressure confined.

Seeds of Life in Space (SOLIS): I. Carbon-chain growth in the Solar-type protocluster OMC2-FIR4

The interstellar delivery of carbon atoms locked into molecules might be one of the key ingredients for the emergence of life. Cyanopolyynes are carbon chains delimited at their two extremities by an atom of hydrogen and a cyano group, so that they might be excellent reservoirs of carbon. The simplest member, HC3N, is ubiquitous in the galactic interstellar medium and found also in external galaxies. Thus, understanding the growth of cyanopolyynes in regions forming stars similar to our Sun, and what affects it, is particularly relevant. In the framework of the IRAM/NOEMA Large Program SOLIS (Seeds Of Life In Space), we have obtained a map of two cyanopolyynes, HC3N and HC5N, in the protocluster OMC2-FIR4. Because our Sun is thought to be born in a rich cluster, OMC2-FIR4 is one of the closest and best known representatives of the environment in which the Sun may have been born. We find a HC3N/HC5N abundance ratio across the source in the range ~ 1 - 30, with the smallest values ( 10 MeV) particles from embedded sources. We suggest that these sources could lie East of FIR4 and FIR5. A temperature gradient across FIR4, with T decreasing by about 10 K, could also explain the observed change in the HC3N/HC5N line ratio, without the need of a cosmic ray ionisation rate gradient. However, even in this case, a high constant cosmic-ray ionisation rate (of the order of