Appeal for "Sweet
Spot" Telescope Observations (1- to 2-meters)
We need better photometric monitoring than I can provide
with an amateur 14-inch telescope. I'm limited to 1-minute
exposures with SNR that is only sufficient for characterizing 5%
dips (that last for 10 minutes or longer). Brief observations
with large telescopes reveal the presence of 1% dip structure
with 10-second temporal variations. There's a "sweet spot" for
telescope size that will allow good SNR while permitting full
orbit (4.5-hour) observing sessions at weekly intervals. I think
that sweet spot aperture is 1 to 2 meters. This is an appeal for
someone to take the lead in obtaining telescope time with a 1 to
2-meter telescope for weekly 5-hour observing sessions for the
duration of the 2017/18 observing season (now to June).
Thin cirrus overcast makes data dubious. I've concluded that
this data should be "rejected."
This is the first observation of the season. All data is at hgh
air mass and the session is short.
WD1145 is at 11:48:33.59 +01:28:59.3 (J2000). FOV = 27 x 18
'arc, northeast at upper left.
Please don't ask me to co-author a paper! At my age of 77
I'm entitled to have fun and avoid work. Observing and figuring
things out is fun. Writing papers is work. Besides, most people
really don't care about what others have done. (Google "WD
1145+017" and among the several pages of lame links none point
to my web pages.)
My light curve observations will be "in the public domain" for
this observing season (2017/18). This includes a download of all
LC observations, which I invite anyone to use. If my data is
essential to any publication just mention this in the
acknowledgement section (no co-authorship, please).
Data Exchange Files
Data exchange files are available in two formats: light curve
details (normalized flux for each image) and dip statistics
(asymmetric hypersecant model fits for each dip). The first of
these is available for download here, but I recommend that
anyone using these data check with me for updates (since I
sometimes find errors and post the corrected files here). Data
exchange files of the second format (dip stat's) will be
available here in due time.
Light curve data
exchange file for 2016.01.27 to 2016.07.13 download: Link (fluxes
for every exposure) Light curve data exchange file for
2016.10.25 to 2017.04.30 download: Link(fluxes
for every exposure) References
Vanderburg, Andrew and Saul A. Rappaport, 2018,
"Transiting Disintegrating Debris around WD 1145+017," arXiv
Rappaport, S. B. L. Gary, A. Vanderburg, S. Xu,
D. Pooley & K. Mukai, "WD 1145+017: Optical Activity During
2016-2017 and Limits on the X-Ray Flux," MNRAS,
Xu, S., S. Rappaport, R. van Lieshout & 35
others, "A dearth of small particles in the transiting material
around the white dwarf WD 1145+017," MNRASlink,
Vanderburg et al, 2015, "A Disintegrating
Minor Planet Transiting a White Dwarf," Nature, 2015 Oct 22,
Croll et al, 2105, "Multiwavelength
Transit Observations of the Candidate Disintegrating Planetesimal
Orbiting WD 1145+017," ApJ, arXiv:1510.06434
Gaensicke et al, 2015, "High-Speed Photometry of
the Disintegrating Planetesimal at WD 1145+017: Evidence for Rapid
Dynamical Evolution," arXiv
Rappaport, S., B. L. Gary, T. Kaye, A.
Vanderburg, B. Croll, P. Benni & J. Foote, 2016, "Drifting
Asteroid Fragments Around WD 1145+017," MNRAS, arXiv:1602.00740
Alonso, R., S. Rappaport, H. J. Deeg and E.
Palle, 2016, "Gray Transits of WD 1145+017 Over the Visible Band," Astron.
& Astrophys., arXiv:1603.08823
Petit, J.-M and M. Henon, 1986, Icarus, 66,
Veras, Dimitri, Philip J. Carter, Zoe M.
Leinhardt and Boris T. Gansicke, 2016, arXiv
Gary, B. L., S. Rappaport, T. G. Kaye, R. Alonso
and F.-J. Hamsch, "WD 1145+017 Photometric Observations During Eight
Months of High Activity," 2017, MNRAS, 465,
Hallakoun, N., S. Xu, D. Maoz, T.R. Marsh, V. D.
Ivanov, V. S. Dhillon, M. C. P. Bours, S. G. Parsons, P. Kerry, S.
Sharma, K. Su, S. Rengaswamy, P. Pravec, P. Kusnirak, H. Kucakova,
J. D. Armstrong, C. Arnold, N. Gerard, L. Vanzi, 2017, Earth and
Planetary Astrophysics, arXiv
Farihi, J., L. Fossati, P. J. Wheatley, B. D.
Metzger, J. Mauerhan, S. Bachman, B. T. Gansicke, S. Redfield, P. W.
Cauley, O. Kochukhov, N. Achilleos & N. Stone, "Magnetism,
X-ras, and Accretion Rates in WD 1145+017 and other Polluted White
Dwarf Systems, MNRAS, arXiv
Tom Kaye presentation at 2016 Society for
Astronomical Science meeting: link