Related papers: A Substellar Mass Function for Alpha Per
We are conducting a proper-motion survey for young brown dwarfs in the Taurus-Auriga molecular cloud based on the Pan-STARRS1 3$\pi$ Survey. Our search uses multi-band photometry and astrometry to select candidates, and is wider (370…
We report on a multi-band survey for very low-mass stars and brown dwarfs in the Lupus 3 cloud with the Wide Field Imager (WFI) at the ESO/MPG 2.2m telescope on La Silla Observatory (Chile). Our multiband optical photometry is combined with…
We present the results of a H- and K-band multi-object and long-slit spectroscopic survey of substellar mass candidates in the outer regions of the Orion Nebula Cluster. The spectra were obtained using MOIRCS on the 8.2-m Subaru telescope…
Monte Carlo simulations of the field substellar mass function (MF) are presented. Starting from various representations of the MF below 0.1 M$_{\sun}$ and the stellar birth rate, luminosity functions (LFs) and T$_{eff}$ distributions are…
We present the results of a survey of the low mass star and brown dwarf population of the 25 Orionis group. Using optical photometry from the CIDA Deep Survey of Orion, near IR photometry from the Visible and Infrared Survey Telescope for…
Recent studies of the substellar population in the Taurus cloud have revealed a deficit of brown dwarfs (BD) compared to the Trapezium cluster population (Briceno et al 1998; Luhman 2000; Luhman et al 2003a; Luhman 2004). However, these…
The substellar initial mass function (IMF) and the formation mechanisms of brown dwarfs (BDs) remain key open questions in star formation theory. IMF characterization in a large number of star-forming regions (SFRs) is essential for…
Our aim is to identify brown dwarf members of the nearby Hyades open star cluster to determine the photometric and spectroscopic properties of brown dwarfs at moderately old ages and extend the knowledge of the substellar mass function of…
Studies of fundamental parameters of very low-mass objects are indispensable to provide tests of stellar evolution models that are used to derive theoretical masses of brown dwarfs and planets. However, only objects with dynamically…
The census of solar neighbours is still complemented by new discoveries, mainly of very low-mass, faint dwarfs, close to or within the substellar domain. These discoveries contribute to a better understanding of the field population; its…
We report the first results of our ongoing campaign to discover the first brown dwarfs (BD) in NGC 2264, a young (3 Myr), populous star forming region for which our optical studies have revealed a very high density of potential candidates -…
We report our efforts to constrain the form of the low-mass star and brown dwarf mass function via Bayesian inference. Recent surveys of M, L, and T dwarfs in the local solar neighborhood are an essential component of our study.…
We have determined possible cluster members of the nearby open cluster Praesepe (M44) based on J and K photometry and proper motions from the PPMXL catalogue and z photometry from the Sloan Digital Sky Survey (SDSS). In total we identified…
Whilst there is a generally accepted evolutionary scheme for the formation of low-mass stars, the analogous processes when moving down in mass to the brown dwarfs regime are not yet well understood. In this first paper we try to build the…
The stellar initial mass function at high redshift is an important defining property of the first stellar systems to form and may also play a role in various dark matter problems. We here determine the faint stellar luminosity function in…
We have observed a large sample of spectroscopic binary stars in the Hyades Cluster, using high resolution infrared spectroscopy to detect low mass companions. We combine our double-lined infrared measurements with well constrained orbital…
We have identified a large sample of probable low mass members of the young open cluster IC2391 based on optical (VRIZ) and Infrared (JHK$_s$) photometry. Our sample includes 50 probable members and 82 possible members, both very low mass…
RCW 38 is a deeply embedded young (~1 Myr), massive star cluster located at a distance of 1.7 kpc. Twice as dense as the Orion Nebula Cluster, orders of magnitude denser than other nearby star forming regions, and rich in massive stars, RCW…
We present the initial results from a survey for planetary-mass brown dwarfs in the Taurus star-forming region. We have identified brown dwarf candidates in Taurus using proper motions and photometry from several ground- and space-based…
Intermediate resolution (R=7000) spectroscopy is presented for 76 photometrically selected very low mass (0.04<M<0.3M_{sun}) candidate members of the Sigma Orionis cluster. More than two thirds appear to be genuine cluster members on the…