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TIFR Near Infrared Imaging Camera-II (TIRCAM2) is being used at the 3.6-m Devasthal Optical Telescope (DOT) operated by Aryabhatta Research Institute of Observational Sciences (ARIES), Nainital, Uttarakhand, India. Earlier, the TIRCAM2 was used at the main port of the DOT on time-shared basis. It has now been installed at the side port of the telescope. Side port installation allows near simultaneous observations with the main port instrument as well as longer operating periods. Thus, the TIRCAM2 serves the astronomical community for a variety of observations ranging from lunar occultations, transient events and normal scheduled observations. [ABSTRACT FROM AUTHOR]

LDN1415-IRS, a low-mass young stellar object (YSO), went into an outburst between 2001 and 2006, illuminating a surrounding nebula, LDN1415-Neb. LDN1415-Neb was found to have brightened by I = 3.77 mag by April 2006. The optical light curve covering ∼ 15.5 years, starting from October 2006 to January 2022, is presented in this study. The initial optical spectrum indicated the presence of winds in the system, but the subsequent spectra have no wind indicators. The declining light curve and the absence of the P-Cygni profile in later epoch spectra indicate that the star and nebula system is retrieving back from its outburst state. Two Herbig–Haro objects (HHOs) are positioned linearly with respect to the optical brightness peak of the nebula, probably indicating the circumstellar disk being viewed edge-on. Our recent deep near-infrared (NIR) imaging using TANSPEC has revealed the presence of a nearby star-like source, south of the LDN1415-IRS, at an angular distance of ∼ 5. 4 ′ ′ . [ABSTRACT FROM AUTHOR]

TIFR Near Infrared Imaging Camera-II (TIRCAM2) is being used at the Devasthal Optical Telescope (DOT) operated by Aryabhatta Research Institute of Observational Sciences (ARIES), Nainital, Uttarakhand, India. In addition to the normal full frame observations, there has been a requirement for high speed sub-array observations for applications, such as lunar occultation and star speckle observations. Fast sub-array modes have been implemented in TIRCAM2 with suitable changes in the camera software at the computer and controller DSP code level. Successful observations have been carried out with the fast sub-array mode of observation. [ABSTRACT FROM AUTHOR]

Using optical photometric observations from 1.3-m Devasthal Fast Optical Telescope and deep near-infrared (NIR) photometric observations from TANSPEC mounted on 3.6-m Devasthal Optical Telescope, along with the multi-wavelength archival data, we present our study of open cluster Kronberger 55 to understand the star-formation scenario in the region. The distance, extinction and age of the cluster Kronberger 55 are estimated as ∼ 3.5 kpc, E (B - V) ∼ 1.0 mag and ≲ 5 Myr, respectively. We identified Young Stellar Objects (YSOs) based on their excess infrared (IR) emission using the two-color diagrams (TCDs). The mid-infrared (MIR) images reveal the presence of extended structure of dust and gas emission along with the outflow activities in the region with two peaks, one at the location of cluster Kronberger 55 and another at 5 ′. 35 southwards to it. The association of radio continuum emission with the southern peak, hints towards the formation of massive star/s. The Herschel sub-millimeter maps reveal the presence of two clumps connected with a filamentary structure in this region, and such configuration is also evident in the 12 CO(1–0) emission map. Our study suggests that this region might be a hub-filament system undergoing star formation due to the 'end-dominated collapse scenario'. [ABSTRACT FROM AUTHOR]

In recent times, 3.6m Devasthal Optical Telescope (DOT) has been installed with an optical to near infra-red spectrograph, TANSPEC, which provides spectral coverage from 0.55 to 2.5 microns. Using TANSPEC, we have obtained a single epoch spectrum of a set, containing nine FUors and EXors. We have analysed line profiles of the sources and compared them with the previously published spectra of these objects. Comparing the line profile shapes with the existing theoretical predictions, we have tried to interpret the physical processes that are responsible for the current disc evolution and the present accretion dynamics. Our study has shown the importance of time-evolved spectroscopic studies for a better understanding of the evolution of the accretion a mechanisms. This in turn can help in the better characterization of the young stars displaying episodic accretion behavior. [ABSTRACT FROM AUTHOR]

We have performed a detailed analysis on the Teutsch 76 (T76) open cluster using the deep near-infrared (NIR) observations taken with the TANSPEC instrument mounted on the 3.6m Devasthal optical telescope along with the recently available high quality proper motion data from the Gaia data release 3 and deep photometric data from Pan-STARRS1 survey. We have found that the T76 cluster is having a central density concentration with circular morphology, probably due to the star-formation processes. The radius of the T76 cluster is found to be 45 ″ (1.24 pc) and 28 stars within this radius were marked as highly probable cluster members. We have found that the cluster is located at a distance of 5.7 ± 1.0 kpc and is having an age of 50 ± 10 Myr. The mass function slope (Γ ) in the cluster region in the mass range of ∼ 0.75 < M / M ⊙ < 5.8 is estimated as - 1.3 ± 0.2 , which is similar to the value of −1.35 given by Salpeter (1955). The cluster is not showing any signatures of mass-segregation and is currently undergoing dynamical relaxation. [ABSTRACT FROM AUTHOR]

We present a study of the molecular cloud in Sh2-112 massive star forming region using the 3-2 transition of CO isotopologues: CO, 13 CO and C 18 O; supplemented in part by CGPS H i line emission and MSX data. Sh2-112 is an optically visible region powered by an O8V type massive star BD + 45 3216, and hosts two Red MSX Survey sources: G083.7962 + 03.3058 and G083.7071 + 03.2817, classified as H ii region and young stellar object, respectively. Reduced spectral data products from the James Clerk Maxwell Telescope archive, centered on the two RMS objects with ∼ 7 ′ × 7 ′ field-of-view each, were utilized for the purpose. The 13 CO(3-2) channel map of the region shows the molecular cloud to have filamentary extensions directed away from the massive star, which also seems to be at the edge of a cavity like structure. Multiple molecular cloud protrusions into this cavity structure, host local peaks of emission. The integrated emission map of the region constructed from only those emission clumps, detected above 5 σ level in the position–position–velocity space affirms the same. MSX sources were found distributed along the cavity boundary, where the gas has been compressed. Spectral extraction at these positions yielded high Mach numbers and low ratios of thermal to non-thermal pressures, suggesting a dominance of supersonic and non-thermal motion in the cloud. [ABSTRACT FROM AUTHOR]

TIFR-ARIES Near Infrared Spectrometer (TANSPEC) instrument provides simultaneous wavelength coverage from 0.55 to 2.5 μ m, mounted on India's largest ground-based telescope, 3.6-m Devasthal Optical Telescope at Nainital, India. The TANSPEC offers three modes of observations, imaging with various filters, spectroscopy in the low-resolution prism mode with derived R ∼ 100 –400 and the high-resolution cross-dispersed mode (XD-mode) with derived median R ∼ 2750 for a slit of width 0.5 arcsec. In the XD-mode, 10 cross-dispersed orders are packed in the 2048 × 2048 pixels detector to cover the full wavelength regime. As the XD-mode is most utilized as well as for consistent data reduction for all orders and to reduce data reduction time, a dedicated pipeline is essential. In this paper, we present the code for the TANSPEC XD-mode data reduction, its workflow, input/output files and a showcase of its implementation on a particular dataset. This publicly available pipeline pyTANSPEC is fully developed in Python and includes nominal human intervention only for the quality assurance of the reduced data. Two customized configuration files are used to guide the data reduction. The pipeline creates a log file for all the fit files in a given data directory from its header, identifies correct frames (science, continuum and calibration lamps) based upon the user input, offers an option to the user for eyeballing and accepting/removing of the frames, does the cleaning of raw science frames and yields final wavelength calibrated spectra of all orders simultaneously. [ABSTRACT FROM AUTHOR]

The infrared astronomy group of the Department of Astronomy and Astrophysics at Tata Institute of Fundamental Research has been pursuing astronomical instrumentation activities since its inception. The group has been routinely involved in a balloon-borne astronomy program from field station at Hyderabad with indigenously developed payloads. Ground-based astronomical activities began with a single element infrared detector. Later, over time, larger format array detectors are being used in the cameras. These astronomy cameras have been routinely used at observatories across India. Recently, the group has also developed a laboratory model of the infrared spectroscopic imaging survey payload, targeted for the small satellite mission of the Indian Space Research Organisation, which will carry out spectroscopic measurements in the wavelength range 1.7–6.4 μ m seamlessly. [ABSTRACT FROM AUTHOR]

We present far ultraviolet (FUV) observations of globular cluster NGC 4147 using three FUV filters, BaF 2 (F154W), sapphire (F169M), and silica (F172M) of Ultra-Violet Imaging Telescope (UVIT) on-board the AstroSat satellite. We confirmed the cluster membership of the UVIT observed sources using proper motions from Gaia data release 2 (GAIA DR2). We identified 37 blue horizontal branch stars (BHBs), one blue straggler star (BSS) and 15 variable stars using UV-optical color magnitude diagrams (CMDs). We find that all the FUV bright BHBs are second generation population stars. Using UV-optical CMDs, we identify two sub-populations, BHB1 and BHB2, among the UV-bright BHBs in the cluster with stars count ratio of 24:13 for BHB1 and BHB2. The effective temperatures ( T eff ) of BHB1 and BHB2 were derived using color-temperature relation of BaSTI-IAC zero-age horizontal branch (ZAHB). We found that BHB1 stars are more centrally concentrated than BHB2 stars. We also derive physical parameters of the detected FUV bright BSS by fitting younger age BaSTI-IAC isochrones on optical and UV-optical CMDs. [ABSTRACT FROM AUTHOR]

The structure of our Galaxy has been studied from ultraviolet (UV) star counts obtained with the Ultra-Violet Imaging Telescope (UVIT) on board the AstroSat satellite, in Far-UV (FUV) and Near-UV (NUV) bands. The F154W (BaF2) and N263M (NUVB4) filters were used in the FUV and NUV bands, respectively. The point sources are separated from the extra-galactic sources of UVIT observations using infrared (IR) color cut method. The observed UVIT star counts match well with the simulations obtained from the Besançon model of stellar population synthesis towards several Galactic directions. We also estimated the scale length and scale height of the thick disc and the scale height of the thin disc using the space density function and the exponential density law for the stars of intermediate galactic latitudes. The scale length of the thick disc ranges from 3.11 to 5.40 kpc whereas the scale height ranges from 530 ± 32 pc to 630 ± 29 pc. The scale height of the thin disc comes out to be in the range of 230 ± 20 pc to 330 ± 11 pc. [ABSTRACT FROM AUTHOR]

The two articles from the Proceedings of the IAU Symposium on Planetary Nebulae referred to as Bianchi et al. (2012a) and Bianchi et al. (2012b) in the original article should have been cited as Bianchi (2012) and Bianchi et al. (2012), respectively, and the entries in the References section should have included the correct information shown below. References Bianchi, L.: In: Manchado, A., Stanghellini, L., Schonberner, D. (eds.) Proceedings of the IAU Symposium, Planetary Nebulae: An Eye to the Future, vol. 283, p. 45 (2012) Bianchi, L., Manchado, A., Forster, K.: In: Manchado, A., Stanghellini, L., Schonberner, D. (eds.) Proceedings of the IAU Symposium, Planetary Nebulae: An Eye to the Future, vol. 283, p. 308 (2012) [ABSTRACT FROM AUTHOR]

We present the ultraviolet (UV) imaging observation of planetary nebulae (PNe) using archival data of Galaxy Evolution Explorer (GALEX). We found 358 PNe detected by GALEX in near-UV (NUV). We have compiled a catalogue of 108 extended PNe with sizes greater than 8 ″ and provided the angular diameters for all the 108 extended PNe in NUV and 28 in FUV from the GALEX images considering 3 σ surface brightness level above the background. Of the 108 PNe, 74 are elliptical, 24 are circular and 10 are bipolar in NUV with most being larger in the UV than in the radio, H α or optical. We derived luminosities for 33 PNe in FUV ( L FUV ) and 89 PNe in NUV ( L NUV ) and found that most of the sources are very bright in UV. The FUV emission of the GALEX band includes contribution from prominent emission lines N IV] (1487 Å), C IV (1550 Å), and O III] (1661 Å) whereas the NUV emission includes C III] (1907 Å) and C II (2325 Å) for PNe of all excitation classes. The other emission lines seen in low excitation PNe are O IV] (1403 Å) and N III (1892 Å) in FUV, and O II (2470 Å) and Mg II (2830 Å) in NUV. Similarly the emission lines O V (1371 Å) and He II (1666 Å) strongly contribute in FUV for high and medium excitation PNe but not for low excitation PNe. A mixture of other emission lines seen in all excitation PNe. We have also provided images of 34 PNe in NUV and 9 PNe in FUV. [ABSTRACT FROM AUTHOR]