Abekta | অবেক্ত

Department of Physical Sciences

Sidebar

Named after Abyakta by Jagadish Chandra Bose.

Physics

Mathematics

A knowledge-base of the Department of Physical Sciences, Independent University, Bangladesh.

jc:12

2020-10-15: Detecting TiO in the spectrum of the hot jupiter WASP-76b

Student presentation on the ongoing work as part of a summer internship at Leiden University, The Netherlands.

Speaker: Fahim Rajit Hossain Shwadhin, a third-year undergraduate student of EEE at Bangladesh Army University of Engineering & Technology (BAUET), Natore.

In the summer of 2020, I had an opportunity to attend my first Astronomy research internship in Leiden University (The Leiden/ESA Astrophysics Program for Summer Students, (LEAPS) with Aurora Kesseli and Alex Cridland acting as my supervisors on the evolution of the exoplanetary Atmospheres. I have been offered the J. Mayo Scholarship at Leiden Observatory.

We looked into the hot Jupiter WASP-76b using High Resolution Spectroscopy (HRS) with the data observed by CARMENES. The method used is transmission spectroscopy. Transmission spectroscopy of exoplanetary atmospheres routinely reveals light chemical species, such as H$_2$O, Na, and K. Heavier molecules, such as Titanium Oxide (TiO) and Vanadium Oxide, have long been predicted to be present in the hottest exoplanetary atmospheres, but definitive detections of these species have been proven to be elusive. It has been predicted that metal oxides such as TiO and Vanadium Oxide occur in the observable regions of the hottest exoplanetary atmospheres causing thermal inversions on the dayside.

Our objective was to compare our observation with the already found signatures of TiO in Low Resolution Spectroscopy (LRS). Previously, some studies found that there is in fact sign of TiO which was detected using LRS but it was noticed that when we do multi-resolution examination the results sometimes become conflicted and vague. So in our project we had decided to use HRS to confirm the existence of TiO and some other species. Multi-resolution spectroscopic observations are highly valuable in characterizing exoplanetary atmospheres and, hence, in understanding their formation history and evolution.

During our study we used a cross correlation method to retrieve any signature of TiO with our predicted model at a certain temperature. Our study at this point found that there are some signs of TiO also H2O but to explain something more vividly we’re cross checking with different cross-correlation templates and a python package called SYSREM.