Related papers: An FUor-like Outbursting Class I Protostar in NGC …
Context. In August 2010, the sudden optical brightening of two young stellar objects, located in the North America/Pelican Nebula Complex, was announced. Early observations indicated that these objects may belong to the FUor or EXor class…
Gaia19fct is one of the Gaia-alerted eruptive young stars that has undergone several brightening events. We conducted monitoring observations using multi-filter optical and near-infrared photometry, as well as near-infrared spectroscopy, to…
Absorption and emission lines originating from the nu3 C-H stretching manifold of gas phase CH4 were discovered in the high resolution (R=25,000) infrared L band spectrum along the line of sight toward NGC 7538 : IRS9. These observations…
We present HST optical images and UV spectra, as well as ground-based near-infrared images of the high surface brightness giant HII region NGC 2363 (NGC 2366-I) and its surroundings. The massive star content of the southern end of the dwarf…
CSS J102913+404220 is a peculiar narrow line Seyfert 1 galaxy with an energetic nuclear optical outburst. We present a detailed analysis of its multi-wavelength photometric and spectroscopic observations covering a period of decade since…
A0538-66 is a Be/X-ray binary (Be/XRB) hosting a 69 ms pulsar. It emitted bright X-ray outbursts with peak luminosity up to $\sim 10^{39}$ erg/s during the first years after its discovery in 1977. Since then, it was always seen in…
One of the most attractive events in the pre-main sequence evolution is the FU Orionis (FUor) outburst. Because only a small number of FUor stars have been detected to date, photometric and spectral studies of every new object are of great…
We report an exceptional mid-infrared flare in the Seyfert 1.8 NGC 3786. In the multi-epoch data from the Wide-field Infrared Survey Explorer, the nuclear mid-infrared brightness of NGC 3786 appears to vary substantially up to $0.5-0.8$ mag…
IGR J17511-3057 was observed in a new outburst phase starting in February 2025 and lasting at least nine days. We investigated the spectral and temporal properties of IGR J17511-3057, aiming to characterise its current status and highlight…
NGC 253 hosts the nearest nuclear starburst. Previous observations show a region rich in molecular gas, with dense clouds associated with recent star formation. We used ALMA to image the 350 GHz dust continuum and molecular line emission…
FU Orionis objects (FUors) are rapidly-accreting, pre-main sequence objects that are known to exhibit large outbursts at optical and near-infrared wavelengths, with post-eruption, small-scale photometric variability superimposed on…
We have obtained high resolution mid-infrared images of the high mass protostar NGC 7538 IRS 1 using Michelle on Gemini North and find that the circumstellar dust associated with this source is extended on both large and small scales. The…
The earliest phases of star formation are characterised by intense mass accretion from the circumstellar disk to the central star. One group of young stellar objects, the FU Orionis-type stars exhibit accretion rate peaks accompanied by…
We present the results of a near-IR spectroscopic survey of 110 Class I protostars observed from 0.80 microns to 2.43 microns at a spectroscopic resolution of R=1200. We find that Class I objects exhibit a wide range of lines and the…
FU Orionis-type objects (FUors) are young low-mass stars undergoing powerful accretion outbursts. The increased accretion is often accompanied by collimated jets and energetic, large-scale molecular outflows. The extra heating during the…
Large-amplitude accretion outbursts in young stars are expected to play a central role in proto-stellar assembly. Outburst identification historically has taken place using optical techniques, but recent, systematic infrared searches are…
The modest extinction and reasonably face-on viewing geometry make the luminous IR galaxy NGC1614 an ideal laboratory for study of a powerful starburst. HST/NICMOS observations show: 1.) deep CO stellar absorption, tracing a starburst…
We present sub-arcsecond (FWHM ~ 0".7), NIR JHKs-band images and a high sensitivity radio continuum image at 1280 MHz, using SIRIUS on UH 88-inch telescope and GMRT. The NIR survey covers an area of ~ 24 arcmin^2 with 10-sigma limiting mags…
The optical time-domain astronomy has grown rapidly in the past decade but the dynamic infrared sky is rarely explored. Aiming to construct a sample of mid-infrared outburst in nearby galaxies (MIRONG), we have conducted a systematical…
Deep optical photometric data on the NGC 7538 region were collected and combined with archival data sets from $Chandra$, 2MASS and {\it Spitzer} surveys in order to generate a new catalog of young stellar objects (YSOs) including those not…