TY - JOUR

T1 - A method to deconvolve stellar rotational velocities

AU - Curé, Michel

AU - Rial, Diego F.

AU - Christen, Alejandra

AU - Cassetti, Julia

N1 - Funding Information:
This work has been partially supported by project CONICT-Redes 12-0007. M.C. thanks the support of FONDECYT project 1130173 and Centro de Astrofísica de Valparaíso. J.C. thanks the financial support from project: “Ecuaciones Diferenciales y Análisis Numérico” – Instituto de Ciencias, Instituto de Desarrollo Humano e Instituto de Industria – Universidad Nacional de General Sarmiento. D.R. acknowledges support from project PIP11420090100165, CONICET. A.C. thanks the support from Instituto de Estadística, Pontificia Universidad Católica de Valparaíso.

PY - 2014/5

Y1 - 2014/5

N2 - Aims. Rotational speed is an important physical parameter of stars, and knowing the distribution of stellar rotational velocities is essential for understanding stellar evolution. However, rotational speed cannot be measured directly and is instead the convolution between the rotational speed and the sine of the inclination angle v sin i. Methods. We developed a method to deconvolve this inverse problem and obtain the cumulative distribution function for stellar rotational velocities extending the work of Chandrasekhar & Münch (1950, ApJ, 111, 142) Results. This method is applied: a) to theoretical synthetic data recovering the original velocity distribution with a very small error; and b) to a sample of about 12.000 field main-sequence stars, corroborating that the velocity distribution function is non-Maxwellian, but is better described by distributions based on the concept of maximum entropy, such as Tsallis or Kaniadakis distribution functions. Conclusions. This is a very robust and novel method that deconvolves the rotational velocity cumulative distribution function from a sample of v sin i data in a single step without needing any convergence criteria.

AB - Aims. Rotational speed is an important physical parameter of stars, and knowing the distribution of stellar rotational velocities is essential for understanding stellar evolution. However, rotational speed cannot be measured directly and is instead the convolution between the rotational speed and the sine of the inclination angle v sin i. Methods. We developed a method to deconvolve this inverse problem and obtain the cumulative distribution function for stellar rotational velocities extending the work of Chandrasekhar & Münch (1950, ApJ, 111, 142) Results. This method is applied: a) to theoretical synthetic data recovering the original velocity distribution with a very small error; and b) to a sample of about 12.000 field main-sequence stars, corroborating that the velocity distribution function is non-Maxwellian, but is better described by distributions based on the concept of maximum entropy, such as Tsallis or Kaniadakis distribution functions. Conclusions. This is a very robust and novel method that deconvolves the rotational velocity cumulative distribution function from a sample of v sin i data in a single step without needing any convergence criteria.

KW - Methods:analytical

KW - Methods:data analysis

KW - Methods:numerical

KW - Methods:statistical

KW - Stars:fundamental parameters

KW - Stars:rotation

UR - http://www.scopus.com/inward/record.url?scp=84900819448&partnerID=8YFLogxK

U2 - 10.1051/0004-6361/201323344

DO - 10.1051/0004-6361/201323344

M3 - Article

AN - SCOPUS:84900819448

VL - 565

JO - Astronomy and Astrophysics

JF - Astronomy and Astrophysics

SN - 0004-6361

M1 - A85

ER -