Astronomers study star cluster KMHK 1762 in the Large Magellanic Cloud

Utilizing the VLT Survey Telescope (VST), European astronomers have studied a specific star cluster within the Massive Magellanic Cloud (LMC), often known as KMHK 1762. The outcomes of the research have been printed July 19 on arXiv.org.

KMHK 1762 (often known as OHSC 37) is a star cluster within the LMC. The cluster has a metallicity at a stage of -0.91 and is estimated to be round 2.7 billion years outdated. Nonetheless, an evaluation of the color-magnitude diagram (CMD) of KMHK 1762 means that the cluster could also be older than at present estimated.

A workforce of astronomers led by Massimiliano Gatto from the Capodimonte Astronomical Observatory in Naples, Italy, investigated this query, speculating that KMHK 1762 may be a uncommon case of a star cluster within the age hole. says LMC. Earlier LMC observations have proven that this galaxy has an nearly full absence of star clusters between 4 and 10 billion years outdated. Inside this age hole, solely two confirmed star clusters have been identified to this point.

Gatto’s workforce analyzed deep optical photometry of KMHK 1762 obtained with VST as a part of the Sure, Magellanic Clouds Once more (YMCA) survey. The research was supplemented by information from ESA’s Gaia satellite tv for pc.

“On this letter, we report the results of our new research of KMHK 1762 SC [star cluster]primarily based on deep and correct YMCA photometry, supplemented with parallaxes and correct motions (PM) from Gaia Early Information Launch 3 (EDR3),” the researchers wrote.

In response to the brand new research, the suitable age of KMHK 1762 must be greater than beforehand thought. Based mostly on shallower photometry, astronomers estimate this cluster to be round 5.5 billion years outdated. Which means KMHK 1762 is the third star cluster within the LMC age hole, along with clusters ESO121-03 and KMHK 1592.

Observations revealed that KMHK 1762 has a redness of about 0.08 magazine and its metallicity is at a stage of -0.65. The CMD reveals a cluster of stars recognized as Principal Sequence Flip-off (MSTO), Subgiant Department (SGB) stars, in addition to just a few stars within the Pink Big Department (RGB) and Pink Group (RC ).

The invention made by the authors of the paper calls into query the existence of star cluster age discrepancy in LMC. They counsel that the elevated variety of confirmed or suspected clusters fashioned through the age-gap interval signifies that the age-gap could also be an observational bias, because of the mixture of shallow photometry and a restricted survey of the LMC’s outer areas.

“The truth is, a lot of the work dedicated to the seek for undiscovered star clusters has been concentrated within the central areas of the LMC leaving the periphery (i.e. d > 4 kpc) fairly unexplored and has been carried out primarily based on shallow photometric surveys, permitting researchers to detect solely star clusters smaller than ∼1–1.5 Gyrs,” the researchers concluded.

© 2022 Science X Community