# Mass function

Mass function

Mass function may refer to:

• Initial mass function, a function that describes the mass distribution of a population of stars in terms of their initial mass
• Probability mass function, a function that gives the probability that a discrete random variable is exactly equal to some value

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• Initial mass function — The initial mass function (IMF) is an empirical function that describes the mass distribution (the histogram of stellar masses) of a population of stars in terms of their theoretical initial mass (the mass they were formed with). The properties… …   Wikipedia

• Probability mass function — In probability theory, a probability mass function (abbreviated pmf) is a function that gives the probability that a discrete random variable is exactly equal to some value. A pmf differs from a probability density function (abbreviated pdf) in… …   Wikipedia

• Initial Mass Function — Die Ursprüngliche Massenfunktion, auch Anfängliche Massenfunktion, englisch Initial Mass Function IMF, beschreibt, wie in einer neu entstehenden Sternpopulation die Verteilung der Sternmassen aussieht. Edwin Salpeter leitete 1955 erstmals die… …   Deutsch Wikipedia

• probability mass function — noun A function that gives the relative probability that a discrete random variable is exactly equal to some value …   Wiktionary

• initial mass function — noun a relationship that specifies the mass distribution of a newly formed stellar population …   Wiktionary

• Mass distribution — For other uses, see Weight distribution. Mass distribution is a term used in physics and mechanics and describes the spatial distribution of mass within a solid body. In principle, it is relevant also for gases or liquids, but on earth their mass …   Wikipedia

• Mass in special relativity — incorporates the general understandings from the concept of mass energy equivalence. Added to this concept is an additional complication resulting from the fact that mass is defined in two different ways in special relativity: one way defines… …   Wikipedia

• Mass comparison — is a method developed by Joseph Greenberg to determine the level of genetic relatedness between languages. It is now usually called multilateral comparison. The method is generally rejected by linguists (Campbell 2001, p. 45), though it has… …   Wikipedia

• Mass finishing — is a group of manufacturing processes that allow large quantities of parts to be simultaneously finished. The goal of this type of finishing is to burnish, deburr, clean, radius, de flash, descale, remove rust, polish, brighten, surface harden,… …   Wikipedia

• Mass spectrometry — (MS) is an analytical technique that measures the mass to charge ratio of charged particles. It is used for determining masses of particles, for determining the elemental composition of a sample or molecule, and for elucidating the chemical… …   Wikipedia