HR 2562 B

Template:Short description Template:Use dmy dates Template:Infobox planet HR 2562 B is a substellar companion orbiting the star HR 2562. Discovered in 2016 by a team led by Quinn M. Konopacky by direct imaging, HR 2562 B orbits within the inner edge of HR 2562's circumstellar discTemplate:Mdashas of April 2023, it is one of only two known brown dwarfs to do so. Separated by roughly Template:Convert from its primary companion, HR 2562 B has drawn interest for its potential dynamical interactions with the outer circumstellar disc.

Discovery

HR 2562 B was discovered using the Gemini Planet Imager (GPI), which first observed the star HR 2562 in January 2016. In the initial data set, Konopacky and collaborators identified a candidate companion object. As a result, followup observations were conducted within the following month in the infrared K1-, K2-, and J-bands. Within the processed data set, HR 2562 B was confirmed to share a common proper motion with HR 2562, with Konopacky and collaborators announcing its discovery in a paper published on 14 September 2016.

Host star

Template:CSS image crop HR 2562 B's parent star, HR 2562 (alternatively designated HD 50571 or HIP 32775), has a mass of Template:Val Template:Solar mass and a radius of Template:Val Template:Solar radius. With an estimated effective temperature of 6597 ± 81K, it is a main-sequence star with the spectral type F5V. It is located Template:Convert from the Sun in the constellation Pictor.Template:Efn HR 2562 is not known to belong to a moving group or stellar cluster.

As with many mid F-type stars, the age of HR 2562 is poorly constrained. Between 1999 and 2011, estimates from various teams of astronomers determined ages ranging from roughly 300 Myr to 1.6 Gyr. In 2018, a team of astronomers led by D. Mesa derived an age of Template:Val Myr using measurements of the star's lithium-temperature relationship.

Properties

Orbital properties

Initial observations of HR 2562 B by Konopacky and collaborators yielded a separation of Template:Convert, placing it interior to and coplanar with the inner edge of HR 2562's observed debris disc. Further observations of HR 2562 B by the Atacama Large Millimeter Array (ALMA) supported this, yielding a semi-major axis of Template:Val AU, an orbital period of Template:Val yr, and an orbital eccentricity of Template:Val. With a probable orbital inclination of Template:Val°, HR 2562 B's misalignment angle with the debris disc is either Template:Val° or Template:Val°. However, the limited coverage of observations still leaves a wide range of possible orbits; both low-eccentricity, coplanar orbits and high-eccentricity, misaligned orbits would be consistent with observation data. However, a highly misaligned orbit would significantly perturb the disc, suggesting that a low-eccentricity, coplanar solutions are likelier.

Any additional companions around HR 2562 with a mass on the order of 10 Template:Jupiter mass should be visible at separations larger than 10 AU, and any companion a few times more massive than Jupiter should be visible to SPHERE's infrared dual-band spectrograph (IRDIS) instrumentTemplate:Mdashthus placing mass restrictions on any additional companions.

Physical properties

HR 2562 B's exact mass is unknown. The brown dwarf was estimated to be 29 ± 15 Template:Jupiter mass in 2021. However, subsequent observations placed an upper mass limit of < 18.5 Template:Jupiter mass. Its luminosity is about $\frac{1}{50000}$ solar luminosity.Template:Refn Its spectral type is L7±3.

See also

• PZ Telescopii B, another substellar object with mass slightly below Template:Jupiter mass