HD 97048 or CU Chamaeleontis is a Herbig Ae/Be star 603 ly away in the constellation Chamaeleon. It is a variable star embedded in a dust cloud containing a stellar nursery, and is itself surrounded by a dust disk.

HD 97048
Observation data
Epoch J2000      Equinox J2000
Constellation Chamaeleon
Right ascension 11h 08m 03.3106s[1]
Declination −77° 39′ 17.4912″[1]
Apparent magnitude (V) 8.38 - 8.48[2]
Characteristics
Evolutionary stage Herbig Ae/Be[3]
Spectral type A0Vep[4]
Variable type INA[2]
Astrometry
Radial velocity (Rv)34.00±2.5[5] km/s
Proper motion (μ) RA: −22.437±0.061[1] mas/yr
Dec.: 1.305±0.059[1] mas/yr
Parallax (π)5.4105 ± 0.0388 mas[1]
Distance603 ± 4 ly
(185 ± 1 pc)
Absolute magnitude (MV)+2.47[6]
Details
Mass2.5[3] M
Radius1.7[7] R
Luminosity33[7] L
Surface gravity (log g)4.30[7] cgs
Temperature10,500[7] K
Age3[3] Myr
Other designations
CD−76 488, HIP 54413, SAO 256802[8]
Database references
SIMBADdata

HD 97048 is a young star still contracting towards the main sequence. Its brightness varies between magnitudes 8.38 and 8.48 and it is classified as an Orion variable.[2] It was given the variable star designation CU Chamaeleontis in 1981.[9] Its spectrum is also variable. The spectral class is usually given as A0 or B9, sometimes with a giant luminosity class, sometimes main sequence. The spectrum shows strong variable emission lines indicative of a shell surrounding the star.[10]

HD 97048 is a member of the Chamaeleon T1 stellar association and is still embedded within the dark molecular cloud that it is forming from. It illuminates a small reflection nebula against the dark cloud.[11]

Planetary system

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This star has a substantial dust disk having a central cavity with a 40−46 AU radius[3] The disk has a carbon monoxide gas velocity kink and intensity gap at 130 AUs, which is suspected to be caused by a superjovian planet.[12] In 2019, HCO+ ion and Hydrogen cyanide emission was detected from the disk, suggesting a large amount of gas is orbiting beyond 200 AU radius.[13]

 
Velocity kink for the CO gas and gap in the disk, showing the presence of a protoplanet

In the system a kink in the velocity of carbon monoxide gas (CO 3–2) as well as a gap in the dust emission of the disk are seen as evidence for a jovian protoplanet. The protoplanet is located at 130 au from the star and has a mass of about 2.5 Jupiter masses. It is one of the lowest mass protoplanets discovered as of 2023.[14]

The HD 97048 planetary system[3][12]
Companion
(in order from star)
Mass Semimajor axis
(AU)
Orbital period
([[]]s)
Eccentricity Inclination Radius
protoplanetary disk 40–850 AU 40°
b 2.5±0.5 MJ 130 40°

References

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  1. ^ a b c d e Brown, A. G. A.; et al. (Gaia collaboration) (August 2018). "Gaia Data Release 2: Summary of the contents and survey properties". Astronomy & Astrophysics. 616. A1. arXiv:1804.09365. Bibcode:2018A&A...616A...1G. doi:10.1051/0004-6361/201833051. Gaia DR2 record for this source at VizieR.
  2. ^ a b c Samus, N. N.; Durlevich, O. V.; et al. (2009). "VizieR Online Data Catalog: General Catalogue of Variable Stars (Samus+ 2007-2013)". VizieR On-line Data Catalog: B/GCVS. Originally Published in: 2009yCat....102025S. 1. Bibcode:2009yCat....102025S.
  3. ^ a b c d e van der Plas, G.; et al. (January 2017). "Cavity and other radial substructures in the disk around HD 97048". Astronomy & Astrophysics. 597: 19. arXiv:1609.02488. Bibcode:2017A&A...597A..32V. doi:10.1051/0004-6361/201629523. S2CID 54495153. A32.
  4. ^ Irvine, N. J.; Houk, N. (1977). "Spectral changes in the pre-main-sequence star HD 97048". Publications of the Astronomical Society of the Pacific. 89: 347. Bibcode:1977PASP...89..347I. doi:10.1086/130131.
  5. ^ Gontcharov, G. A. (2006). "Pulkovo Compilation of Radial Velocities for 35 495 Hipparcos stars in a common system". Astronomy Letters. 32 (11): 759–771. arXiv:1606.08053. Bibcode:2006AstL...32..759G. doi:10.1134/S1063773706110065. S2CID 119231169.
  6. ^ Anderson, E.; Francis, Ch. (2012). "XHIP: An extended hipparcos compilation". Astronomy Letters. 38 (5): 331. arXiv:1108.4971. Bibcode:2012AstL...38..331A. doi:10.1134/S1063773712050015. S2CID 119257644.
  7. ^ a b c d Fairlamb, J. R.; Oudmaijer, R. D.; Mendigutía, I.; Ilee, J. D.; Van Den Ancker, M. E. (2015). "A spectroscopic survey of Herbig Ae/Be stars with X-shooter - I. Stellar parameters and accretion rates". Monthly Notices of the Royal Astronomical Society. 453 (1): 976. arXiv:1507.05967. Bibcode:2015MNRAS.453..976F. doi:10.1093/mnras/stv1576. S2CID 55938596.
  8. ^ "HD 97048". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2019-01-23.
  9. ^ Kholopov, P. N.; Samus', N. N.; Kukarkina, N. P.; Medvedeva, G. I.; Perova, N. B. (1981). "65th Name-List of Variable Stars". Information Bulletin on Variable Stars. 1921: 1. Bibcode:1981IBVS.1921....1K.
  10. ^ Skiff, B. A. (2014). "VizieR Online Data Catalog: Catalogue of Stellar Spectral Classifications (Skiff, 2009-2014)". VizieR On-line Data Catalog: B/Mk. Originally Published in: Lowell Observatory (October 2014). 1. Bibcode:2014yCat....1.2023S.
  11. ^ Rydgren, A. E. (1980). "Observations of young stars in the association Chamaeleon T1". The Astronomical Journal. 85: 444. Bibcode:1980AJ.....85..444R. doi:10.1086/112694.
  12. ^ a b Pinte, C.; Van Der Plas, G.; Ménard, F.; Price, D. J.; Christiaens, V.; Hill, T.; Mentiplay, D.; Ginski, C.; Choquet, E.; Boehler, Y.; Duchêne, G.; Perez, S.; Casassus, S. (2019). "Kinematic detection of a planet carving a gap in a protoplanetary disk". Nature Astronomy. 3 (12): 1109–1114. arXiv:1907.02538. Bibcode:2019NatAs...3.1109P. doi:10.1038/s41550-019-0852-6. S2CID 195820690.
  13. ^ Booth, Alice S.; Walsh, Catherine; Ilee, John D. (2019). "First detections of H13CO+ and HC15N in the disk around HD 97048". Astronomy & Astrophysics. 629: A75. arXiv:1907.08060. doi:10.1051/0004-6361/201834388. S2CID 197544948.
  14. ^ Pinte, C.; van der Plas, G.; Ménard, F.; Price, D. J.; Christiaens, V.; Hill, T.; Mentiplay, D.; Ginski, C.; Choquet, E.; Boehler, Y.; Duchêne, G.; Perez, S.; Casassus, S. (2019-08-01). "Kinematic detection of a planet carving a gap in a protoplanetary disk". Nature Astronomy. 3 (12): 1109–1114. arXiv:1907.02538. Bibcode:2019NatAs...3.1109P. doi:10.1038/s41550-019-0852-6. ISSN 2397-3366. S2CID 195820690.