The Star Formation History and Mass Function of the Double Cluster h and χ Persei

  title={The Star Formation History and Mass Function of the Double Cluster h and $\chi$ Persei},
  author={C. Slesnick and L. Hillenbrand and P. Massey},
  journal={The Astrophysical Journal},
The h and χ Per "double cluster" is examined using wide-field (0°.98 × 0°.98) CCD UBV imaging supplemented by optical spectra of several hundred of the brightest stars. Restricting our analysis to near the cluster nuclei, we find identical reddenings [E(B-V) = 0.56 ± 0.01], distance moduli (11.85 ± 0.05), and ages (12.8 ± 1.0 Myr) for the two clusters. In addition, we find an initial mass function slope for each of the cluster nuclei that is quite normal for high-mass stars, Γ = -1.3 ± 0.2… Expand
The Stellar Population of h and χ Persei: Cluster Properties, Membership, and the Intrinsic Colors and Temperatures of Stars
From photometric observations of {approx} 47,000 stars and spectroscopy of {approx} 11,000 stars, we describe the first extensive study of the stellar population of the famous Double Cluster, h andExpand
Physical Properties of the B and Be Star Populations of h and χ Persei
We present a study of the B and Be star populations of the double cluster h and χ Persei. Blue optical spectroscopy is used to first measure projected rotational velocity, V sin i, effective surfaceExpand
B Star Rotational Velocities in h and χ Persei: A Probe of Initial Conditions during the Star Formation Epoch?
Projected rotational velocities (v sin i) have been measured for 216 B0–B9 stars in the rich, dense h and χ Persei double cluster and compared with the distribution of rotational velocities for aExpand
The Unusual Initial Mass Function of the Arches Cluster
As a young massive cluster in the Central Molecular Zone, the Arches cluster is a valuable probe of the stellar Initial Mass Function (IMF) in the extreme Galactic Center environment. We useExpand
Substructure and halo population of Double Cluster h and χ Persei
In order to study the stellar population and possible substructures in the outskirts of Double Cluster $h$ and $\chi$ Persei, we investigate using the GAIA DR2 data a sky area of about 7.5 degrees inExpand
Spitzer IRAC and JHKS observations of h and χ persei: Constraints on protoplanetary disk and massive cluster evolution at ∼107 years
We describe IRAC 3.6-8 μm observations and ground-based near-IR JHKs photometry from Mimir and 2MASS of the massive double cluster h and χ Persei complete to J = 15.5 (M ~ 1.3 M☉). Within 25' of theExpand
Structure and Mass Segregation in h and χ Persei
We use V magnitudes and spectral types to examine the density structure of h and χ Per. We describe an automatic method for deriving spectral types and compare classifications for observations madeExpand
The birth-cluster of the galactic luminous blue variable WRA 751
We present the results of NTT/VLT UBV imaging of a 260 arcmin 2 region containing the Galactic Luminous Blue Variable WRA 751, in search for its birth-cluster, i.e. a cluster of young and massiveExpand
Fifty Years of IMF Variation: The Intermediate-Mass Stars
I track the history of star count estimates of the Milky Way field star and open cluster IMFs, concentrating on the neglected mass range from 1 to 15 M� .T he prevalent belief that the IMF isExpand
A Deep Spitzer Survey of Circumstellar Disks in the Young Double Cluster, h and chi Persei
We analyze very deep IRAC and MIPS photometry of $\sim$ 12,500 members of the 14 Myr old Double Cluster, h and $\chi$ Persei, building upon on our earlier, shallower Spitzer studies (Currie et al.Expand


Photometric study of the double cluster h and chi Persei
We present uvbybeta CCD photometry of the central region of the double cluster h and chi Persei. We identify 350 stars, of which 214 were not included in Oosterhof catalogue. Our magnitude limitExpand
The Intermediate-Mass Population in the Core of the R136 Star Cluster*
R136, the compact, luminous star cluster at the center of the 30 Doradus nebula, represents an extreme mode of star formation. Yet it is unique among these kinds of objects in that it can be resolvedExpand
A Preliminary Study of the Orion Nebula Cluster Structure and Dynamics
We use optical and near-infrared star counts to explore the structure and dynamics of the Orion Nebula Cluster (ONC). This very young (<1 Myr) cluster is not circularly symmetric in projection but isExpand
Mass segregation in young compact star clusters in the Large Magellanic Cloud — II. Mass functions
We review the complications involved in the conversion of stellar luminosities into masses and apply a range of mass-to-luminosity relations to our Hubble Space Telescope observations of the youngExpand
The Progenitor Masses of Wolf-Rayet Stars and Luminous Blue Variables Determined from Cluster Turnoffs. I. Results from 19 OB Associations in the Magellanic Clouds
We combine new CCD UBV photometry and spectroscopy with those from the literature to investigate 19 Magellanic Cloud OB associations that contain Wolf-Rayet (W-R) and other types of evolved, massiveExpand
The Initial Mass Function and Massive Star Evolution in the OB Associations of the Northern Milky Way
We investigate the massive star content of Milky Way clusters and OB associations in order to answer three questions: (1) How coeval is star formation? (2) How constant is the initial mass functionExpand
Grids of pre-main sequence stellar models. The accretion scenario at Z=0.001 and Z=0.020
I present and briefly discuss a new set of pre-main sequence (MS) evolutionary tracks computed in the framework of the accretion paradigm for star formation at metallicities Z=0.001 and Z=0.020.Expand
Studies of luminous stars in nearby galaxies. I. Supergiants and O stars in the Milky Way.
In this paper the fundamental properties of the brightest known stars in our Galaxy are determined for future comparison with results for the most luminous stars in other galaxies. The H-R diagramsExpand
MK spectral types for 185 bright stars.
A program has been initiated at the Yerkes Observatory to determine more accurately the mean direction of the interstellar magnetic field in the vicinity of the sun by observing the interstellarExpand
Model Atmospheres for Population Synthesis
I have used my newly calculated iron group line list together with my earlier atomic and molecular line data, 58,000,000 lines total, to compute new opacities for the temperature range 2000K toExpand