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I

Infrared

(Last edited: Friday, 28 April 2023, 6:09 PM)

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Short Definition:

Light with wavelength from 800 nanometers to 1 millimiter.

Detailed Definition:

Electromagnetic radiation with wavelengths ranging from 800 nanometers to one millimeter. It is next to the red end of the visible spectrum, hereby the name. Also called IR, it is a kind of electromagnetic radiation that has qualities like both a wave and a particle, the photon, and propagates energy and momentum as well as exerting radiation pressure.

Etymology:

Infrared comes from Latin: infra, which means below.

Sample Sentence(s):

To keep an eye on workplace activities, they used infrared cameras.

Without disturbing the bats, an infrared camera records them.

Translations of Terms/Concepts into Partner Languages

French: infrarouge

German: Infrarot

Polish: podczerwień

Swedish: infraröd

Links to Videos/Articles:

https://science.nasa.gov/ems/07_infraredwaves

https://education.nationalgeographic.org/resource/infrared-vision



Initial mass function (IMF)

(Last edited: Friday, 28 April 2023, 6:09 PM)

Plot initial mass function with different alpha values

Image source:

https://upload.wikimedia.org/wikipedia/commons/thumb/d/d5/Plot_of_various_initial_mass_functions.svg/800px-Plot_of_various_initial_mass_functions.svg.png


Short Definition:

The initial mass function (IMF) describes the distribution of stellar masses as a large cluster of stars is newly formed and is based on an average from stars in our Milky Way.

This function is useful for understanding the formation of stellar systems and their evolution. In most cases, the initial mass function is shown with a logarithmic scale.

Derailed Definition:

The initial mass function shows few massive stars which are more massive than the sun, while sun-sized stars are more abundant and stars that are smaller than the sun are quite common (this trend does not continue linear the smaller they get):

The function can be described by using the following law:

IMF = constant x m^(-α)

where m = initial star mass and α = slope of the logarithmic plot.

Until this point in time, it is not certain if the IMF varies in extreme situations and if the calculation based on our Milky Way can be unconditionally applied to other galaxies.


Etymology:

initial - Latin initialis ("initial, incipent, of the beginning")

mass - old French masse (" lump, heap, pile; crowd, large amount")

function - Latin functionem (" a performance, an execution")


Sample sentences:

There are different curve forms of the initial mass function based on the way the alpha and the constant are calculated.


Translation:

French: fonction de masse initiale

German: Anfangsmassenfunktion

Polish:początkowafunkcjamasy

Swedish: funktion för dem ursprungliga massan


Links to Videos/Articles:

http://astro1.physics.utoledo.edu/~megeath/ph6820/lecture12_eqn.pdf
http://www.astro.yale.edu/larson/papers/Nagoya99.pdf
https://www.cfa.harvard.edu/news/initial-mass-function
https://www.youtube.com/watch?v=V5WlgcBh9T8