We present simultaneous optical and near-infrared (NIR) polarimetric results for the black hole binary V404 Cyg spanning the duration of its seven-day-long optically brightest phase of its 2015 June outburst. The simultaneous R-and K s -band light curves showed almost the same temporal variation except for the isolated (∼30-minute duration) orphan K s -band flare observed at MJD 57193.54. We did not find any significant temporal variation of polarization degree (PD) and position angle (PA) in both R and K s bands throughout our observations, including the duration of the orphan NIR flare. We show that the observed PD and PA are predominantly interstellar in origin by comparing the V404 Cyg polarimetric results with those of the surrounding sources within the 7′ × 7′ field of view. The low intrinsic PD (less than a few percent) implies that the optical and NIR emissions are dominated by either disk or optically thick synchrotron emission, or both. We also present the broadband spectra of V404 Cyg during the orphan NIR flare and a relatively faint and steady state by including quasi-simultaneous Swift/XRT and INTEGRAL fluxes. By adopting a single-zone synchrotron plus inverse-Compton model as widely used in modeling of blazars, we constrained the parameters of a putative jet. Because the jet synchrotron component cannot exceed the Swift/XRT disk/corona flux, the cutoff Lorentz factor in the electron energy distribution is constrained to be <10 2 , suggesting that particle acceleration is less efficient in this microquasar jet outburst compared to active galactic nucleus jets. We also suggest that the loading of the baryon component inside the jet is inevitable based on energetic arguments.

We present the early-phase spectra and the light curves of the broad-lined supernova (SN) 2016coi from t = 7 to 67 days after the estimated explosion date. This SN was initially reported as a broadlined Type SN Ic (SN Ic-BL). However, we found that spectra up to t = 12 days exhibited the He i λ5876, λ6678, and λ7065 absorption lines. We show that the smoothed and blueshifted spectra of normal SNe Ib are remarkably similar to the observed spectrum of SN 2016coi. The line velocities of SN 2016coi were similar to those of SNe Ic-BL and significantly faster than those of SNe Ib. Analyses of the line velocity and light curve suggest that the kinetic energy and the total ejecta mass of SN 2016coi are similar to those of SNe Ic-BL. Together with broad-lined SNe 2009bb and 2012ap for which the detection of He i were also reported, these SNe could be transitional objects between SNe Ic-BL and SNe Ib, and be classified as broad-lined Type 'Ib' SNe (SNe 'Ib'-BL). Our work demonstrates the diversity of the outermost layer in broad-lined SNe, which should be related to the variety of the evolutionary paths. Subject headings: supernovae: general -supernovae: individual (SN 2016coi) -supernovae: individual (SNe

Polarization during a lunar eclipse is a forgotten mystery. Coyne & Pellicori (1970) reported the detection of significant polarization during the lunar eclipse on 1968 April 13. Multiple scattering during the first transmission through the Earth's atmosphere was suggested as a possible cause of the polarization, but no conclusive determination was made. No further investigations on polarization during a lunar eclipse are known. We revisit this mystery with an interest in possible application to extrasolar planets; if planetary transmitted light is indeed polarized, it may be possible to investigate an exoplanet atmosphere using "transit polarimetry." Here we report results of the first spectropolarimetry for the Moon during a lunar eclipse on 2015 April 4. We observed polarization degrees of 2-3 % at wavelengths of 500-600 nm; in addition, an enhanced feature was detected at the O 2 A band near 760 nm. The observed time variation and wavelength dependence are consistent with an explanation of polarization caused by double scattering during the first transmission through the Earth's atmosphere, accompanied by latitudinal atmospheric inhomogeneity. Transit polarimetry for exoplanets may be useful to detect O 2 gas and to probe the latitudinal atmospheric inhomogeneity, and it is thus worthy of serious consideration.

The results of a spectroscopic survey of Hα emission line stars associated with fourteen bright rimmed clouds are presented. Slit-less optical spectroscopy was carried out with the Inter University Centre for Astronomy and Astrophysics (IUCAA) 2 m telescope and IUCAA Faint Object Spectrograph and Camera (IFOSC). Hα emission line was detected from 173 objects. Among them 85 objects have a strong Hα emission line with its equivalent width larger than 10 Å. Those are classical T Tauri stars. 52 objects have a weak Hα emission line with its equivalent width less than 10 Å and do not show intrinsic near-infrared excess. Those are weak-line T Tauri stars. On the other hand, 36 objects have a weak Hα emission line (<10 Å), although they show intrinsic near-infrared excess. Such objects are not common in low-mass star forming regions. Those are misfits of the general concept on formation process of a low-mass star, in which it evolves from a classical T Tauri star to a weak-line T Tauri star. Those might be weak-line T Tauri stars with a flared disk in which gas is heated by ultraviolet radiation from a nearby early-type star. Alternatively, we propose pre-transitional disk objects as their evolutional stage.

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