Search
Text Size:
Smaller Text Normal Text Larger Text

Facebook page

Twitter profile

YouTube channel

Zero polarisation standards

NEW: Highly accurate DIPOL measurements of low-polarisation stars are found in Piirola et al. 2020, A&A 635, A46 High-precision polarimetry of nearby stars (d < 50 pc)
A selection is to be added to our ZP standard star list (TBD) and a few are listed below in the format of TCS catalogs. Note the high proper motions and the bright V magnitude.

HD4813    00 50 07.59 -10 38 39.6 2000.0 -0.2269 -0.2298 5.19   P=0.0006%
HD18144   02 55 17.41 +16 18 33.1 2000.0  0.2043 -0.0466 6.9    P=0.0008%
HD42182   06 09 35.91 +05 40 08.1 2000.0  0.0588  0.0465 8.38   P=0.0028%
HD65629   07 59 53.39 +09 53 55.3 2000.0  0.1239 -0.1510 7.8    P=0.0014%
HD191195  20 06 13.85 +53 09 56.5 2000.0  0.2133  0.2551 5.7    P=0.0039%

New and fainter (13 mag < R < 17 mag) zero-pol standards may be found from the source list of white dwarfs observed with RoboPol by Zejmo et al. 2017, MNRAS 464, 1294. See online table .

The below catalogue can be loaded to the TCS by typing read-cat zpol.cat in the TCS terminal.
Name
TCSTGT
RA (2000) DEC (2000) V B-V Sp. Type PB (%) Comment
HD 12021
HD12021
01 57 56.11 -02 05 58.2 8.86 -0.10 B7 0.112 ± 0.025
 
HD 14069
HD14069
02 16 45.16 07 41 11.1 9.00
  
A0 0.111 ± 0.036
 
HD 21447
HD21447
03 30 00.21 55 27 07.0 5.10 +0.04 A1 IV 0.017 ± 0.030 ND filter #5 (1 % transmission)
G191B2B
G191B2B
05 05 30.62 52 49 54.0 11.78 -0.30 DA1 0.090 ± 0.048 Faint. More than 1 cycle a 15 min
needed on Turpol.
HD 64299
HD64299
07 52 25.55 -23 17 45.9 10.15 +0.09 A2 V 0.151 ± 0.032
 
HD 94851
HD94851
10 56 44.17 -20 39 51.6 9.10
  
B9 0.057 ± 0.018 ND filter #6 (open)
GD 319
GD319
12 50 04.49 55 06 02.5 12.32 +0.04 DA 0.045 ± 0.047 Faint. More than 1 cycle a 15 min
needed on Turpol.
NB Binary, separation ~2.6"
BD +33 2642
BDp33_2642
15 51 59.86 32 56 54.8 10.84 -0.17 B2 IV 0.145 ± 0.029 ND filter #6 (open)
HD 154892
HD154892
17 07 41.38 15 12 37.6 8.00
  
F8 V 0.050 ± 0.030
 
BD +32 3739
BDp32_3739
20 12 02.11 32 47 43.5 9.31 +0.20 A6 V 0.039 ± 0.021 ND filter #6 (open)
BD +28 4211
BDp28_4211
21 51 11.07 28 51 51.8 10.53 -0.34 Op 0.063 ± 0.023 ND filter #6 (open)
HD 212311
HD212311
22 21 58.55 56 31 52.8 8.10 +0.08 A0 V 0.028 ± 0.025 ND filter #1 (50% transmission)

Stars suitable for the NOT, taken from The Hubble Space Telescope atlas, see Turnshek et al. 1990, AJ 99, 1243.

Finding charts from the Digital Sky Survey are obtained by clicking on the star names. These have North up and East left, are centred on the star, and the field size is 6.5 arc minutes (i.e. ALFOSC field with no calcite plate in the beam).


The visibility plot of today:


Minimum observing altitude when lower hatch closed: 35 degrees.

Please wait ... Genrating visibility plot

 

Back to top Last modified: June 20 2023