J/A+A/610/A25 Sulamitis and Clarissa asteroids spectra (Morate+, 2018)
Visible spectroscopy of the Sulamitis and Clarissa primitive families:
a possible link to Erigone and Polana
Morate D., de Leon J., De Pra M., Licandro J., Cabrera-Lavers A.,
Campins H., Pinilla-Alonso N.
<Astron. Astrophys. 610, A25 (2018)>
=2018A&A...610A..25M 2018A&A...610A..25M (SIMBAD/NED BibCode)
ADC_Keywords: Minor planets ; Solar system ; Spectra, optical
Keywords: minor planets, asteroids: general - methods: data analysis -
techniques: spectroscopic
Abstract:
The low-inclination (i<80°) primitive asteroid families in the
inner main belt, that is, Polana-Eulalia, Erigone, Sulamitis, and
Clarissa, are considered to be the most likely sources of near-Earth
asteroids (101955) Bennu and (162173) Ryugu. These two primitive NEAs
will be visited by NASA OSIRIS-REx and JAXA Hayabusa 2 missions,
respectively, with the aim of collecting samples of material from
their surfaces and returning them back to Earth. In this context, the
Primitive Asteroid Spectroscopic Survey (PRIMASS) was born, with the
main aim to characterize the possible origins of these NEAs and
constrain their dynamical evolution. As part of the PRIMASS survey we
have already studied the Polana and Erigone collisional families in
previously published works. The main goal of the work presented here
is to compositionally characterize the Sulamitis and Clarissa families
using visible spectroscopy. We have observed 97 asteroids (64 from
Sulamitis and 33 from Clarissa) with the OSIRIS instrument (0.5-0.9um)
at the 10.4m Gran Telescopio Canarias (GTC). We found that about 60%
of the sampled asteroids from the Sulamitis family show signs of
aqueous alteration on their surfaces. We also found that the majority
of the Clarissa members present no signs of hydration. The results
obtained here show similarities between Sulamitis-Erigone, and
Clarissa-Polana collisional families.
Description:
A total of 97 low-resolution visible spectra were obtained for the
asteroids in the Sulamitis and Clarissa families (64 and 33 objects,
respectively), using the Optical System for Imaging and Low Resolution
Integrated Spectroscopy (OSIRIS) camera spectrograph at the 10.4m Gran
Telescopio Canarias (GTC), located at the El Roque de los Muchachos
Observatory (ORM) in La Palma, Canary Islands, Spain.
In addition, we obtained three spectra of (752) Sulamitis using the
Intermediate Dispersion Spectrograph (IDS) at the 2.5m Isaac Newton
Telescope, also located at the ORM in La Palma, as part of program C97
(2015), on July 22, 2015.
All the spectra files included here are named ast_ASTEROIDNUMBER.txt,
except for the spectra of (752) taken with the INT (named
ast752INT.txt). The first column is the wavelength, expressed in
microns, and the second column is the reflectance value (which is
normalized at 1 at 0.55 microns).
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
list.dat 68 98 Observational circumstances for the asteroids
presented in this work
sulamitis/* . 65 Individual spectra of Sulamitis asteroids
clarissa/* . 33 Individual spectra of Clarissa asteroids
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See also:
B/astorb : Orbits of Minor Planets (Bowell+ 2014)
Byte-by-byte Description of file: list.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 6 I6 --- Ast Asteroid number
7 A1 --- n_Ast [*] *: Observed with INT
9- 18 A10 "DD-MM-YYYY" Obs.date Observation date
20- 24 A5 "h:m" Obs.time Observation UT start time
26- 31 A6 s TExp Exposure time
33- 36 F4.1 mag Vmag V magnitude
38- 42 A5 --- SAs ID number of each solar analog star (1)
44- 68 A25 --- FileName Name of the spectrum file
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Note (1): Solar analog stars as follows:
--------------------------------------------
ID Star RA (J2000) DE Vmag
--------------------------------------------
1 = SA 93-101 01:53:18.0 +00:22:25 9.7
2 = SA 98-978 06:51:34.0 -00:11:28 10.5
3 = SA 102-1081 10:57:04.4 -00:13:10 9.9
4 = SA 107-998 15:38:16.4 +00:15:23 10.4
5 = SA 110-361 18:42:45.0 +00:08:04 12.4
6 = SA 112-1333 20:43:11.8 +00:26:15 10.0
7 = SA 115-271 23:42:41.8 +00:45:10 9.7
--------------------------------------------
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Byte-by-byte Description of file: sulamitis/* clarissa/*
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
4- 16 E13.9 um lambda Wavelength
20- 32 E13.9 --- Refl Relative reflectance
(normalized at 1 at 0.55um)
34- 40 F7.5 --- e_Refl ? rms uncertainty on Refl, only for INT spectrum
--------------------------------------------------------------------------------
Acknowledgements:
David Morate, damog(at)iac.es
(End) Patricia Vannier [CDS] 07-Nov-2017