! Proposal 6258, submission 1 ! PI: ! Received Thu Apr 6 19:10:46 EDT 1995 ! From: amanda@lowell.edu ! file: 6258 ! SCCSid: @(#)6258 1.2 4/6/95 Proposal_Information ! Section 4 Title: Is the Chiron Occultation Star, Ch02, a Double? Proposal_Category: GTO/HSP Scientific_Category: Cool Stars ! Uncomment one of the following Cycle: 5 Investigators PI_Name: Robert C. Bless PI_Institution: University of Wisconsin CoI_Name: Amanda S. Bosh CoI_Institution: Lowell Observatory Contact: Y ! Y or N (designate at most one contact) CoI_Name: James L. Elliot CoI_Institution: Massachusetts Institute of Technology Contact: N ! Y or N (designate at most one contact) CoI_Name: Otto G. Franz CoI_Institution: Lowell Observatory Contact: N ! Y or N (designate at most one contact) Abstract: ! Free format text (clear and concise) We observed an occultation of the star Ch02 by Chiron on 1993 November 7 from five locations, but the light curves obtained have defied explanation so far (see IAUC 5898). What we were expecting to see was an occultation by Chiron's nucleus--a sharp drop of the stellar flux to zero that would last a few seconds before abruptly returning to full scale. However, the observed occultation was only 75% of the total starlight. So, either the star is a close double, or Chiron's nucleus has a bizarre structure. The double-star hypothesis will be tested with FGS observations. Questions ! Free format text (clear and concise) Observing_Description: The star Ch02 will be examined for duplicity with the FGS at two epochs. The proposed observations should reach a sensitivity of 0.02 arcsec or duplicity if delta mag is 1.6 which it has to be to explain the incomplete occultation (observed). Two epochs of observations are needed to be sure that the separation of the components is not oriented perpendicular to the measurement of the FGS for a particular epoch. Real_Time_Justification: Calibration_Justification: Additional_Comments: Fixed_Targets ! Section 5.1 Target_Number: 1 Target_Name: CH02 Alternate_Names: GSC0249-00971 Description: STAR Position: RA=10H 28M 08.057S +/- 0.5", DEC=3D 30' 35.748" +/- 0.5", PLATE-ID=01FY Equinox: J2000 RV_or_Z: RA_PM: ! Units are seconds of time per year Dec_PM: ! Units are seconds of arc per year Epoch: Annual_Parallax: Flux: V = 14.3 +/- 0.1, B-V= 1.0 +/- 0.1, V-R= 0.6 +/- 0.1, V-I= 1.2 +/- 0.1 Comments: Finder chart available in Bus et al., AJ 107, 1814. Solar_System_Targets ! Section 5.2 Generic_Targets ! Section 5.3 Scan_Data ! Appendix B ! This is a template for a single visit containing a single exposure ! Repeat exposure and visit blocks as needed Visits ! Section 6 Visit_Number: 1 Visit_Requirements: PCS MODE Fine orient 304d to 306d On_Hold_Comments: Visit_Comments: Exposure_Number: 1 ! Section 6.5 Target_Name: CH02 Config: FGS Opmode: TRANS Aperture: 3 Sp_Element: F583W Wavelength: 5830 Optional_Parameters: DATA-RATE = 32, STEP-SIZE = 1.0, SCANS = 48, ACQ-MODE = SEARCH Number_of_Iterations: 1 Time_Per_Exposure: 1440S Special_Requirements: POS TARG 0.0, 0.0 Comments: This seq will make 48 scans across the star at a scan length of 1.2 arcsec on each interferometric axis in steps of 1 mas. It will repeat the obs at an orient that is + or - 45D (+/-15D). Visit_Number: 2 Visit_Requirements: PCS MODE Fine ORIENT 335D TO 345D On_Hold_Comments: Visit_Comments: Optimal orientation is either +45D or -45D from Visit 1. ORIENT can also be -30D to -60D FROM 1 Exposure_Number: 2 ! Section 6.5 Target_Name: CH02 Config: FGS Opmode: TRANS Aperture: 3 Sp_Element: F583W Wavelength: 5830 Optional_Parameters: DATA-RATE = 32, STEP-SIZE = 1.0, SCANS = 48, ACQ-MODE = SEARCH Number_of_Iterations: 1 Time_Per_Exposure: 1440S Special_Requirements: POS TARG 0.0, 0.0 Comments: Data_Distribution ! Defaults indicated; change if desired Medium: 8MM ! 8MM or 6250BPI or 1600BPI Blocking_Factor: 10 ! 10 or 1 ! Only astronomers with very old 9- ! track tape drives should consider ! a blocking factor of 1 Ship_To: Amanda S. Bosh ! STSCI or PI_Address or Lowell Observatory 1400 W. Mars Hill Road Flagstaff, AZ 86001-4499 Ship_Via: UPS ! UPS (2-day) or OVERNIGHT ! Overnight shipping done at PI expense Recipient_Email: amanda@lowell.edu ! Needed if Ship_To: is not PI_Address !