Time series photometry and multi-wavelength characterisation of the young stellar cluster Mon R2

Abstract

Using the Las Cumbres Observatory Global Telescope Network (LCOGT), we have obtained multi-epoch photometry of the young cluster Mon R2. We have monitored over 6000 sources with $i$-band between 13 and 23 mag within a $26^{\prime }x26^{\prime }$ field of view. For each star, we collected $\sim 1500$ photometric points covering a temporal window of 23 days. Based on these data, we have measured rotation-modulated of 136 stars and identified around 90 additional variables, including 14 eclipsing binary candidates. Moreover, we found 298 other variables with photometric high-scatter. In addition, we have obtained $r$-band and H$\alpha$ narrow-band photometry of the cluster with LCOGT and low-resolution optical spectroscopy of 229 stars with GMOS-Gemini. We used the \textit{Gaia} data from the periodic stars and objects with H$\alpha$ or IR-excesses, which are mostly low-mass pre-main sequence stars ($<1$M${}_{sun}$) in the cluster to estimate the distance ($825\pm 51$ pc) and the mean proper motions (${\mu }_{\alpha }cos(\delta )=-2.75$mas yr${}^{-1}$ and ${\mu }_{\delta }=1.15$mas yr${}^{-1}$) of its members. This allows us to use the \textit{Gaia} data to identify additional Mon R2 member candidates. We also used Pan-STARRS photometry from our LCOGT sources to construct a more precise H-R diagram, from which we estimate the mean age of the cluster and identify other possible members including eleven spectroscopy brown dwarf with M7 to M9 GMOS spectral types. Finally, we combined our membership lists with \textit{Spitzer} infrared photometry to investigate the incidence of stars with discs and the effect these have on stellar rotation.

28 pages, 36 figures, will be published in MNRAS: MN-21-3195-MJ

References in corpus (20)

• Estimating distances from parallaxes. V: Geometric and photogeometric distances to 1.47 billion stars in Gaia Early Data Release 3
• New evolutionary models for pre-main sequence and main sequence low-mass stars down to the hydrogen-burning limit
• Gaia Early Data Release 3: Parallax bias versus magnitude, colour, and position
• A Spitzer Survey of Young Stellar Clusters within One Kiloparsec of the Sun: Cluster Core Extraction and Basic Structural Analysis
• The Optical to Mid-Infrared Extinction Law Based on the APOGEE, Gaia DR2, Pan-STARRS1, SDSS, APASS, 2MASS and WISE Surveys
• Gaia Early Data Release 3 -- Catalogue validation
• Hunting for open clusters in \textit{Gaia} DR2: $582$ new OCs in the Galactic disc
• A Large Catalog of Accurate Distances to Molecular Clouds from PS1 Photometry
• The Monitor project: Rotation of low-mass stars in NGC 2362 -- testing the disc regulation paradigm at 5 Myr
• CSI 2264: Investigating rotation and its connection with disk accretion in the young open cluster NGC 2264
• Rotation of Low-Mass Stars in Taurus with K2
• Exploring open cluster properties with Gaia and LAMOST
• Accretion discs as regulators of stellar angular momentum evolution in the ONC and Taurus-Auriga
• Far-infrared observations of a massive cluster forming in the Monoceros R2 filament hub
• NICMOS/HST Observations of the Embedded Cluster Associated with Mon R2: Constraining the sub-stellar Initial Mass Function
• A ZTF Look at Optical Variability of Young Stellar Objects in the North America and Pelican Nebulae Complex
• Investigating the rotational evolution of young, low mass stars using Monte Carlo simulations
• Variable stars in the Sh 2-170 HII region
• Evidence for disc regulation in the lowest-mass stars of the young stellar cluster NGC 2264
• New Methods for Determining the Ages of PMS Stars