Distance, magnetic field and kinematics of a filamentary cloud LDN 1157

LDN 1157, is one of the several clouds situated in the cloud complex, LDN 1147/1158, represents a coma-shaped morphology with a well-collimated bipolar outflow emanating from a Class 0 protostar, LDN 1157-mm. The main goals of this work are (a) to map the inter-cloud magnetic field (ICMF) geometry of the region surrounding LDN 1157 to investigate its relationship with the cloud morphology, with the outflow direction and with the core magnetic field (CMF) geometry inferred from the mm- and sub-mm polarization results from the literature, and (b) to investigate the kinematic structure of the cloud. We carried out R-band polarization observations of the stars projected on the cloud to map the pc-scale magnetic field geometry and made spectroscopic observations of the entire cloud in 12CO, C18O and N2H+ (J=1-0) lines to investigate its kinematic structure. We obtained a distance of 340$\pm$3 pc to the LDN 1147/1158, complex based on the Gaia DR2 parallaxes and proper motion values of the three YSOs associated with the complex. A single filament of $\sim1.2$ pc in length and $\sim0.09$ pc in width is found to run all along the coma-shaped cloud. Based on the relationships between the ICMF, CMF, filament orientations, outflow direction, and the presence of an hour-glass morphology of the magnetic field, it is likely that the magnetic field had played an important role in the star formation process in LDN 1157. Combining the proper motions of the YSOs and the radial velocity of LDN 1147/1158 and another complex LDN 1172/1174 which is situated $\sim2$\dgr~east of it, we found that both the complexes are moving collectively toward the Galactic plane. The filamentary morphology of the east-west segment of LDN 1157 may have formed as a result of mass lost by ablation due to the interaction of the moving cloud with the ambient interstellar medium.Comment: 20 pages, Accepted in Astronomy & Astrophysics, Abstract has been shortened due to word limit in arxi

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On the collisional disalignment of dust grains in illuminated and shaded regions of IC 63

Interstellar dust grain alignment causes polarization from UV to mm wavelengths, allowing the study of the geometry and strength of the magnetic field. Over the last couple of decades, observations and theory have led to the establishment of the radiative alignment torque mechanism as a leading candidate to explain the effect. With a quantitatively well constrained theory, polarization can be used not only to study the interstellar magnetic field, but also the dust and other environmental parameters. Photodissociation regions, with their intense, anisotropic radiation fields, consequent rapid H2 formation, and high spatial density-contrast provide a rich environment for such studies. Here we discuss an expanded optical, NIR, and mm-wave study of the IC 63 nebula, showing strong H2 formation-enhanced alignment and the first direct empirical evidence for disalignment due to gas-grain collisions using high-resolution HCO+(J = 1-0) observations. We find that a relative amount of polarization is marginally anticorrelated with column density of HCO+. However, separating the lines of sight of optical polarimetry into those behind, or in front of, a dense clump as seen from γ Cas, the distribution separates into two well defined sets, with data corresponding to "shaded" gas having a shallower slope. This is expected if the decrease in polarization is caused by collisions since collisional disalignment rate is proportional to RC∝nT" role="presentation">RC∝nT−−√ . Ratios of the best-fit slopes for the "illuminated" and "shaded" samples of lines of sight agrees, within the uncertainties, with the square root of the two-temperature H2 excitation in the nebula seen by Thi et al.Fil: Soam, Archana. Sofia Science Center; Estados UnidosFil: Anderson, B. G. Sofia Science Center; Estados UnidosFil: Acosta Pulido, Jose. Instituto de Astrofisica de Canarias; EspañaFil: Fernandez Lopez, Manuel. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Instituto Argentino de Radioastronomía. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto Argentino de Radioastronomía; ArgentinaFil: Vaillancourt, J. E.. Lincoln Laboratory; Estados UnidosFil: Widicus Weaver, S. L.. Department Of Chemistry; Estados UnidosFil: Piirola, V.. University Of Turku; FinlandiaFil: Gordon, M. S.. Sofia Science Center; Estados Unido

First Sub-parsec-scale Mapping of Magnetic Fields in the Vicinity of a Very-low-luminosity Object, L1521F-IRS

L1521F is found to be forming multiple cores and it is cited as an example of the densest core with an embedded VeLLO in a highly dynamical environment. We present the core-scale magnetic fields (B-fields) in the near vicinity of the VeLLO L1521F-IRS using submillimeter polarization measurements at 850 mu m using JCMT POL-2. This is the first attempt to use high-sensitivity observations to map the sub-parsec-scale B-fields in a core with a VeLLO. The B-fields are ordered and very well connected to the parsec-scale field geometry seen in our earlier optical polarization observations and the large-scale structure seen in Planck dust polarization. The core-scale B-field strength estimated using the Davis-Chandrasekhar-Fermi relation is 330 +/- 100 mu G, which is more than 10 times the value we obtained in the envelope (the envelope in this paper is the "core envelope"). This indicates that B-fields are getting stronger on smaller scales. The magnetic energies are found to be 1 to 2 orders of magnitude higher than nonthermal kinetic energies in the envelope and core. This suggests that magnetic fields are more important than turbulence in the energy budget of L1521F. The mass-to-flux ratio of 2.3 +/- 0.7 suggests that the core is magnetically supercritical. The degree of polarization is steadily decreasing toward the denser part of the core with a power-law slope of -0.86.Peer reviewe

Enabling hypervisor environment for increasing efficiency and effectiveness of training programmes - a case study at NAARM

The National Academy of Agricultural Research Management (NAARM) was established by the Indian Council of Agricultural Research (ICAR) at Hyderabad, in 1976, to address issues related to agricultural research and education management. The Academy also renders services for building IP portfolios like patents and geographical indications to various stakeholders including farmers and scientists. Keeping in view the increasing national and global need to integrate agriculture with agribusiness for raising rural incomes, and the increased emphasis on the creation, dissemination, application and exchange of knowledge in this vital area, the Academy has recently initiated post graduate education programmes and set up an Agribusiness Knowledge Centre. In the above mentioned scenario, NAARM also conducting many training programmes/courses over the year and there is lot of time and money being invested into purchasing physical machines and software. There is a need of maintaining specific set of software required for each training. The Coordinators of the training programmes has to ensure beforehand that all the machines are working fine and all the software required for that training got installed in all machines and working without any issues. This requirement of preparedness for training programmes has been avoided completely by establishing a private cloud which can provide Infrastructure as a Service (IaaS) at our organization. At the end of programmes may it be a regular or refresher course, coordinators has supposed to be evaluate the participants by tools like quizzes and exams. NAARM is using SynchronEyes Student-Teacher software for evaluation purpose. Many issues were there in this examinations system because of network, virus and power problems. This also has been completely avoided by establishing a hybrid cloud