J band (infrared)

In infrared astronomy, the J band refers to an atmospheric transmission window (1.1 to 1.4 um) centred on 1.25 micrometres (in the near-infrared).

Atmospheric windows in the infrared. The J band is the transmission window (1.1 to 1.4 um) centred on 1.25 micrometres

Betelgeuse is the brightest near-IR source in the sky with a J band magnitude of −2.99.^[1] The next brightest stars in the J band are Antares (−2.7), R Doradus (−2.6), Arcturus (−2.2), and Aldebaran (−2.1).^[2] In the J band Sirius is the 9th brightest star.

The J band is a frequent source of ground based observations since the wavelengths it covers pass through clouds and other atmospheric gasses.^[3] The waveband does however suffer from contamination by water vapor lines and hydroxide emission lines leading to relatively high photometric error.^[4]

It can be used to scrutinize the photosphere of giant and supergiant stars while mostly avoiding opacities from molecular bands and also has access to the 1080 nm He I line which is useful in the study of circumstellar disk interactions around T-Tauri stars.^[5]

References

1. R. Cutri and M. Skrutskie (2009-09-07). "Very Bright Stars in the 2MASS Point Source Catalog (PSC)". The Two Micron All Sky Survey at IPAC. Retrieved 2011-12-28.
2. "Simbad object query:Jmag<-2 & Vmag>-9". SIMBAD Astronomical Database. Retrieved 2012-08-22.
3. "Infrared Astronomy Optical Filters". www.andovercorp.com. Retrieved 2023-04-01.
4. Simons, D. A.; Tokunaga, A. T. (February 2002). "The Mauna Kea Observatories Near-Infrared Filter Set. I: Defining Optimal 1-5 $\mu$m Bandpasses". Publications of the Astronomical Society of the Pacific. 114 (792): 169–179. arXiv:astro-ph/0110594. doi:10.1086/338544. ISSN 0004-6280. S2CID 7880289.
5. Pedretti, Ettore; Piacentini, S.; Corrielli, G.; Osellame, Roberto; Minardi, Stefano (2018-07-09). "A six-apertures discrete beam combiners for J-band interferometry". In Tuthill, Peter G.; Creech-Eakman, Michelle J.; Mérand, Antoine (eds.). Optical and Infrared Interferometry and Imaging VI. Vol. 10701. SPIE. pp. 316–325. arXiv:1809.01260. Bibcode:2018SPIE10701E..16P. doi:10.1117/12.2312033. ISBN 9781510619555. S2CID 119458175.