Spectra of ELG Candidates

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PI: Prochaska

Common:

Goal: We seek mask and longslit spectra of quasar/galaxy pairs to measure ELG redshifts

Starlists: elgs_starlist_feb2018.txt

Necessary Calibrations: We will need arcs, biases, spectral flats with the same setups. Arcs: tilt grating for ELG/QSO slit. Flats: need sky flats for the blue detector.

Conditions: This project can be done in poor seeing conditions, by increasing exposure times. However, pairs with small separation (<2-3") require good seeing conditions. Extinction is not desirable.

Exposure time: We are aiming for 40min of on-source exposure in nominal conditions. I propose 4x 10min exposures on the red-side. You could do 2x 20min on the blue (with small adjustments for the differences in read out times [the blue side is faster]).

Masks:

Mask afternoon (setup):

  1. Confirm slit positions as you take an image of each mask (automated)
  2. Define the alignment boxes (using the Keck tool)
  3. Generate a mask starlist with the WMKO software
  4. On a well-centered mask (e.g. XXX) figure out a good tilt for the grating based on the ELG or QSO slit.

Dichroic

Blue

Red

Red Tilt Wavelength

D560

600/4000

400/8500

XXX

Mask afternoon calibrations:

  1. A 1s and a 3s Arc through each mask; all arc lamps except Fe
  2. 3 dome flat exposures on each camera

Mask Acquisition:

See the LRIS web pages

Longslit:

Longslit Setup:

Dichroic

Blue

Red

Red Tilt Wavelength

slit

D560

600/4000

400/8500

XXX

1"

Longslit Observing Procedure/Exposure Times:

  1. Go to coordinates of the quasar and rotate to given PA
  2. Align the quasar in the slit-B position to put the ELG in the slit as well... Be mindful of slit geometry here. Pairs with separations greater than 10 arcseconds could land in the gap. Either offset or rotate PA + 180.. These will have to be aligned off the center of the slit-B position.

  3. Expose

Longslit Table:

ELG_NAME

RA_GAL

DEC_GAL

RA_QSO

DEC_QSO

NUV

Z_HW

PA

theta

J003411.55-010034.7

8.54812782976

-1.00965032534

8.55435562134

-1.00747704506

18.08

1.29601

70.7601017277

23.7426805376

J081736.11+223714.2

124.400438978

22.6206107232

124.396148682

22.62159729

18.27

0.982203

283.989501138

14.6925855176

J085943.91+411735.0

134.932971534

41.2930417995

134.935882568

41.2888565063

18.22

1.38913

152.407205796

17.0005328684

J090915.76+163514.3

137.315672412

16.5872987907

137.31703186

16.5895862579

17.87

1.07244

29.6642588531

9.47694189775

J091840.94+290640.8

139.67058329

29.1113373892

139.669799805

29.1088485718

18.68

1.37639

195.378486041

9.29245015841

J092755.87+253012.2

141.982790765

25.5033949609

141.987014771

25.5021629333

17.31

1.19583

107.907852394

14.4236376998

J095455.97+174312.0

148.733204122

17.7200115042

148.736755371

17.7253417969

18.18

1.47749

32.3994896439

22.7270229311

J100151.51+275945.3

150.464643909

27.9959201185

150.463928223

28.0006256104

17.39

1.1342

352.35140253

17.091843544

J101810.91+354251.8

154.545444437

35.7143861786

154.54574585

35.7109680176

18.1

1.2294

175.904635122

12.3368796839

J101902.83+101706.2

154.761780059

10.2850665071

154.763031006

10.2819538116

18.07

1.18447

158.424572662

12.0499861256

J103929.38+392355.3

159.872405091

39.3986954516

159.867263794

39.39503479

17.34

1.01153

227.344860338

19.4484719596

J103929.49+392328.3

159.872871366

39.3911832591

159.867263794

39.39503479

17.34

1.01153

311.631281358

20.8720127518

J104230.37+221310.5

160.626560425

22.2195857383

160.629669189

22.2168064117

18.21

1.00749

134.000774957

14.4032372801

J104232.25+221251.1

160.63436569

22.2141849309

160.629669189

22.2168064117

18.21

1.00749

301.088100455

18.2772793838

J104841.15+442803.8

162.171471179

44.467722754

162.164138794

44.472530365

18.16

0.998084

312.579273744

25.5808411322

J112315.84+051806.9

170.816013423

5.30192613879

170.822998047

5.30112123489

17.27

1.00021

96.6014039771

25.2042051598

J114931.29+223004.5

177.380366308

22.5012532951

177.38230896

22.5078811646

17.81

0.962257

15.1510317342

24.7196205974

J121615.59+165236.2

184.064960667

16.8767215226

184.066131592

16.8833599091

18.22

1.19816

9.5803318874

24.2362204508

J125547.85+401236.2

193.949357551

40.2100525232

193.948410034

40.2085571289

18.46

1.08762

205.822306941

5.98056993897

J132852.66+061159.0

202.219428678

6.19971447257

202.225753784

6.19783496857

18.24

1.17663

106.640925689

23.6268219989

J132921.59+144432.5

202.339941382

14.7423557058

202.340621948

14.7420034409

18.67

0.981512

118.156717819

2.68741406197

J133249.03+395804.7

203.20430256

39.9679646182

203.202972412

39.9655838013

17.88

1.15339

203.180676964

9.32362720266

J134843.33+024956.5

207.180523794

2.83235941172

207.186538696

2.83029603958

17.91

1.04478

108.955532497

22.8673052672

J140021.50+433838.2

210.089592492

43.6439470575

210.096252441

43.6477890015

18.13

1.1257

51.435685755

22.1877701029

J145501.25+084957.2

223.755191244

8.83256202738

223.760253906

8.83389759064

18.16

1.10626

75.0518112062

18.6401792839

ElGs (last edited 2018-02-15 03:48:31 by xavier)