HM Lup photometry and spectroscopy requested

Active Dates: May 4, 2023 – June 2, 2023


Abstract:

Antonio Armeni (University of Tuebingen) has requested AAVSO observers' assistance in obtaining photometry and spectroscopy of the classical T Tau star HM Lup in support of observations with TESS scheduled for 2023 May 4 - June 2.

Justification:

HM Lup is a young M-type star that accretes material from a circumstellar disk through a magnetosphere. With its accretion rate of 2.5 · 10−9 M⊙/yr in 2012 (Manara et al. 2022), HM Lup is among the strongest accretors in Lupus. The optical spectrum of HM Lup is rich in emission lines typical of a Classical T Tauri Star. Due to the accretion process, HM Lup is a very active star and it is both photometrically and spectroscopically variable. Therefore, it is essential to study this object using a multi-wavelength approach, by means of simultaneous observations in different spectral regions. Photometric data in the BVRI bands are crucial to study the accretion variability of this target. Spectroscopic observations of selected emission lines, such as Hbeta, He I 5876 + Na I D lines, the Mg I / Fe II lines around 5165-5185 Å, and Fe II 4924 and 5316, would be important to study the structure of the accretion flow.

Requested Data Types:

Photometry, Spectroscopy



Targets
Name Magnitude Variability Type Photometry Notes Spectroscopy Notes
HM Lup 14.45 CTTS

Cadence: Not Specified

Precision: 100

Cadence: Not Specified

Resolution: 250

Desired SNR: 100


Spectroscopy Lines:

No spectroscopy lines provided

Photometry Filters:

No photometry filters provided

Comparison Stars:

No comparison stars provided


Co-Authorship

Observers are not eligible for co-authorship.

Additional Observer Input:

Not provided

Additional Submission Location:

Not provided


Forum URL

N/A


Notes:

Principal Investigator: Antonio Armeni; Imported Campaign (Alert Notice #822)