17223( 3) - 09-Jun-2023 12:33:20 - [ 1] HUBBLE SPACE TELESCOPE OBSERVING PROGRAM 17223 Version: 3 Check-in Time: 09-Jun-2023 12:33:20 STScI Edit Number: 0 Title Far out in the SMC wing: the extraordinary cluster NGC 602 ------------------------------------------------------------------------------------ Type Cycle GO 30 ------------------------------------------------------------------------------------ Investigators Contact? PI: Dr. Peter Zeidler Space Telescope Science Institute - ESA - Y JWST CoI: Dr. Antonella Nota Space Telescope Science Institute N CoI: Dr. Elena Sabbi Space Telescope Science Institute N CoI: Prof. Eva K. Grebel Universitat Heidelberg N CoI: Dr. Monica Tosi INAF-Osservatorio di Astrofisica e Scienza N dello Spazio CoI: Dr. Anna Pasquali Universitat Heidelberg N CoI: Dr. Daniel J. Lennon Instituto de Astrofisica de Canarias N CoI: Dr. Anna Faye McLeod Durham Univ. N ------------------------------------------------------------------------------------ Abstract NGC 602 is a truly extraordinary young star cluster (YSC): located in a very low-density, low-metallicity region in the SMC Bridge it has formed a remarkable stellar content of 10^3 Solar masses and hosts many OB stars similar to Orion. Optical and infrared Hubble and Spitzer observations revealed a large number of disk-bearing, young stars in the cluster center and newly forming Young Stellar Objects embedded in the surrounding clouds. This suggests an age ladder for NGC 602 and that the massive OB stars drive star formation into the clouds. We are proposing to use the unique UV capabilities of Hubble to measure the far-ultra violet (FUV) fluxes and stellar winds of the 12 most massive cluster stars using STIS spectroscopy. Only with HST, it is possible to directly access the FUV flux budget of the entire YSC, to quantify the stellar winds for the most massive O stars. Together with scheduled Cycle 1 Webb data we will establish how efficiently NGC 602 drives star formation outwards, which may lead to an extended star formation period, and how the close proximity to the OB stars influences protoplanetary disk and planet formation and evolution. Furthermore, scheduled VLT/MUSE integral field spectroscopy will enable us to directly study how the FUV fluxes shape the surrounding gas of the HII region. NGC 602, which has a mass budget similar to Orion but is located in a sub-solar metallicity environment, provides the link between star formation and feedback processes under Milky Way conditions, where YSCs are too heavily attenuated for FUV observations, and those in lower-metallicity environments like distant galaxies, where only the most massive stars can be resolved. ------------------------------------------------------------------------------------ Observations Description ------------------------ We plan to observe 11 O and B stars in NGC 602 using STIS FUV MAMA spectroscopy. To calculate the exposure times we used the SpTs of Ramachandran+2019 (obtained 17223( 3) - 09-Jun-2023 12:33:20 - [ 2] with optical VLT/FLAMES spectra). For the remaining two stars we estimated their SpTs using their F555W magnitudes in conjunction with the Castelli-Kurucz spectral atlas. We used the archival STIS data of Sk183 to verify our assumptions and to ensure that we do not exceed the safety limits of the MAMA detector (30, 000 counts/s). To fulfill our science goals, we target a S/N>20 at a reference wavelength of 1500 Angstrom under the condition of not using more than one orbit per star. To avoid undersampling, hot pixels, and to minimize the effects of cosmic rays, we plan to use the STIS-ALONG-SLIT dither strategy with four pointings and a shift of 11 spectral pixels (0.267 arcsec) as recommended by the Cycle 30 STIS instrument handbook (Prichard+ 2022). Where possible we plan to observe always two stars per pointing. We want to use the G140L grating with the 0.5 arcsec, which is a good compromise between spectral purity, defined by the slit width, and to ensure that the two sources fall into the same slit, despite the Hubble pointing inaccuracies. The cluster center is relatively crowded so we plan to do target aquesition on the O3V star (Sk183) with a relative offset to each source. We used the exisiting HST ACS/WFC photoemtry for the target coordinates in the Gaia system (ICRS). We also used these coordinates to calulate the orients as well as the offsets needed to fit two stars in the same slit if applicatable. The visit packing will be the following: STIS-OFFSET-A (visit 28) (1 orbit): The stars O9V-2 and B0.7V will be observed with the same slit. Their estimated combined global count rate is 3, 464 counts/s. Star B1.5(IV)e will be observed in a separate exposure within this visit. STIS-OFFSET-B (visit 29) (3 orbits): The stars O9V-3 and B2.5V will be observed with the same slit. Their estimated combined global count rate is 2, 413 counts/s. The stars B2V-1, B2V-2, and B2V-3 will be observed in separate exposures within this visit. STIS-OFFSET-C (visit 31) (3 orbits): The stars O8.5V and O9V-1 will be observed with the same slit. Star O9V-2 may fall in the same slit. Their combined global count rate is 7, 828 counts/s. The star O7V will be observed in separate exposures within this visit. ------------------------------------------------------------------------------------ 17223( 3) - 09-Jun-2023 12:33:20 - [ 3] TARGET LIST Fixed Targets ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial | Flux data No | Name | Description | Position |Eqnx | Vel. | ------------------------------------------------------------------------------------------------------------------------------------ 11 O3V STAR, MAIN SEQUENCE O RA=01H29M24.5515S, J2000 V = 13.78 +/- 0.01 DEC=-73D33'16.37" Reference Frame: ICRS Extended: NO Comments: The coordinates are in the Gaia reference frame Epoch of Position RA proper motion (seconds of time/yr) DEC Proper Motion (arcsec/yr) Annual Parallax (arcsec) 2016.0 0.0 0.0 0.0 ------------------------------------------------------------------------------------------------------------------------------------ 12 O7V STAR, MAIN SEQUENCE O RA-OFF=8.7283S, J2000 V = 14.143 DEC-OFF=-28.2791", FROM 11 Extended: NO Comments: The coordinates are as offsets from the O3V star and the distance is calulated using the GaiaeDR3 coordinates and in the Gaia reference frame ------------------------------------------------------------------------------------------------------------------------------------ 13 O8.5V.O9V-1 STAR, MAIN SEQUENCE O RA-OFF=6.8278S, J2000 V = 15.463 +/- 0.016 DEC-OFF=-26.1252", FROM 11 Extended: NO Comments: The coordinates are as offsets from the O3V star and the distance is calulated using the GaiaeDR3 coordinates and in the Gaia reference frame. Originally we used the O8.5V star for the ACQ/PEAK but we discovered that this stars is actually two sources. We call them for now O8.5V_a and O8.5V_b. Hence we decided to center on the O9V-1 source instead. We adjusted the POS TARG offset accordingly ------------------------------------------------------------------------------------------------------------------------------------ 14 B1.5IV-E STAR, MAIN SEQUENCE O RA-OFF=3.1896S, J2000 V = 15.368 DEC-OFF=16.7029", FROM 11 Extended: NO Comments: The coordinates are as offsets from the O3V star and the distance is calulated using the GaiaeDR3 coordinates and in the Gaia reference frame ------------------------------------------------------------------------------------------------------------------------------------ 16 O9V-2.B0.7V STAR, MAIN SEQUENCE O RA-OFF=8.2545S, J2000 V = 15.359 DEC-OFF=-22.7938", FROM 11 Extended: NO Comments: The coordinates are as offsets from the O3V star and the distance is calulated using the GaiaeDR3 coordinates and in the Gaia reference frame ------------------------------------------------------------------------------------------------------------------------------------ 17 O9V-3.B2.5V STAR, MAIN SEQUENCE O RA-OFF=7.4078S, J2000 V = 15.543 DEC-OFF=-14.7179", FROM 11 Extended: NO Comments: The coordinates are as offsets from the O3V star and the distance is calulated using the GaiaeDR3 coordinates and in the Gaia reference frame ------------------------------------------------------------------------------------------------------------------------------------ 17223( 3) - 09-Jun-2023 12:33:20 - [ 4] TARGET LIST Fixed Targets ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial | Flux data No | Name | Description | Position |Eqnx | Vel. | ------------------------------------------------------------------------------------------------------------------------------------ 19 B2V-1 STAR, B0-B2 V-IV RA-OFF=8.3605S, J2000 V = 16.136 DEC-OFF=-54.7420", FROM 11 Extended: NO Comments: The coordinates are as offsets from the O3V star and the distance is calulated using the GaiaeDR3 coordinates and in the Gaia reference frame ------------------------------------------------------------------------------------------------------------------------------------ 20 B2V-2 STAR, B0-B2 V-IV RA-OFF=-3.4187S, J2000 V = 16.142 DEC-OFF=10.3374", FROM 11 Extended: NO Comments: The coordinates are as offsets from the O3V star and the distance is calulated using the GaiaeDR3 coordinates and in the Gaia reference frame ------------------------------------------------------------------------------------------------------------------------------------ 21 B2V-3 STAR, B0-B2 V-IV RA-OFF=12.3233S, J2000 V = 16.239 DEC-OFF=-54.1350", FROM 11 Extended: NO Comments: The coordinates are as offsets from the O3V star and the distance is calulated using the GaiaeDR3 coordinates and in the Gaia reference frame ------------------------------------------------------------------------------------------------------------------------------------ 17223( 3) - 09-Jun-2023 12:33:20 - [ 5] Patterns ------------------------------------------------------------------------------------------------------------------------------------ Pattern_Number: 2 Primary_Pattern Secondary_Pattern Pattern_Type STIS-ALONG-SLIT Pattern_Purpose DITHER Number_Of_Points 4 Point_Spacing 0.27 Line_Spacing Coordinate_Frame POS-TARG Pattern_Orient 90.0 Angle_Between_Sides Center_Pattern NO ------------------------------------------------------------------------------------------------------------------------------------ 17223( 3) - 09-Jun-2023 12:33:20 - [ 6] Visit: 28 (STIS-OFFSET-A) Visit Requirements: ORIENT 315.189547D TO 315.189547 D On Hold Comments: Additional Comments: The fixed orient is necessary tp fit two stars simulatniously in one slit. This method saves more 5 orbits in total Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exp | Target | Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Num | Name | Config | Mode | or FOV |Element |Waveln.| Parameters |Exp| (Total) | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 O3V STIS/CCD ACQ F28X50LP MIRROR 1 0.2 S (0.2 S) ------------------------------------------------------------------------------------------------------------------------------------ 2 O3V STIS/CCD ACQ/PEA 52X0.1 MIRROR 1 0.2 S (0.2 K S) ------------------------------------------------------------------------------------------------------------------------------------ 3 O9V-2.B0.7V STIS/FUV ACCUM 52X0.5 G140L 1425 1 225 S (900 POS TARG 0, -2; PATTERN -MAMA S) 2 3 Comments: The ETC Run # for the other star in the slit is:STIS.sp.1864808 The combined global count rate is: 4496 far below the saftly limits. ------------------------------------------------------------------------------------------------------------------------------------ 4 B1.5IV-E STIS/FUV ACCUM 52X0.5 G140L 1425 1 250 S POS TARG 0, 3; PATTERN 2 -MAMA (1000 S) 4 ------------------------------------------------------------------------------------------------------------------------------------ Sub Exposures ------------------------------------------------------------------------------------------------------------------------------------ Target | Exp |Instr | Oper. | Aper |Spectral|Cent.|Primary |Secondary |Iteration |CR-SPLIT |Orbit |Duration Name | Num |Config | Mode | or FOV |Element |Wave.|Pattern Pos |Pattern Pos |Num |Num |Number | ------------------------------------------------------------------------------------------------------------------------------------ O3V 1 STIS/CCD ACQ F28X50LP MIRROR none none none none 1 N/A O3V 2 STIS/CCD ACQ/PEA 52X0.1 MIRROR none none none none 1 N/A K O9V-2.B0.7V 3 STIS/FUV ACCUM 52X0.5 G140L 1425 1 none none none 1 N/A -MAMA O9V-2.B0.7V 3 STIS/FUV ACCUM 52X0.5 G140L 1425 2 none none none 1 N/A -MAMA O9V-2.B0.7V 3 STIS/FUV ACCUM 52X0.5 G140L 1425 3 none none none 1 N/A -MAMA O9V-2.B0.7V 3 STIS/FUV ACCUM 52X0.5 G140L 1425 4 none none none 1 N/A -MAMA B1.5IV-E 4 STIS/FUV ACCUM 52X0.5 G140L 1425 1 none none none 1 N/A -MAMA B1.5IV-E 4 STIS/FUV ACCUM 52X0.5 G140L 1425 2 none none none 1 N/A -MAMA B1.5IV-E 4 STIS/FUV ACCUM 52X0.5 G140L 1425 3 none none none 1 N/A -MAMA B1.5IV-E 4 STIS/FUV ACCUM 52X0.5 G140L 1425 4 none none none 1 N/A -MAMA 17223( 3) - 09-Jun-2023 12:33:20 - [ 7] Visit: 29 (STIS-OFFSET-B) Visit Requirements: ORIENT 340.089743D TO 340.089743 D On Hold Comments: Additional Comments: The fixed orient is necessary tp fit two stars simulatniously in one slit. This method saves more 5 orbits in total Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exp | Target | Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Num | Name | Config | Mode | or FOV |Element |Waveln.| Parameters |Exp| (Total) | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 O3V STIS/CCD ACQ F28X50LP MIRROR 1 0.2 S (0.2 S) ------------------------------------------------------------------------------------------------------------------------------------ 2 O3V STIS/CCD ACQ/PEA 52X0.1 MIRROR 1 0.2 S (0.2 K S) ------------------------------------------------------------------------------------------------------------------------------------ 3 O9V-3.B2.5V STIS/FUV ACCUM 52X0.5 G140L 1425 1 520 S POS TARG 0, -2; PATTERN -MAMA (2080 S) 2 3 Comments: The ETC Run # for the other star in the slit is: STIS.sp.1332724 The combined global count rate is: 5735 far below the safty limits. ------------------------------------------------------------------------------------------------------------------------------------ 4 B2V-1 STIS/FUV ACCUM 52X0.5 G140L 1425 1 419 S POS TARG 0, 5; PATTERN 2 -MAMA (1676 S) 4 ------------------------------------------------------------------------------------------------------------------------------------ 5 B2V-2 STIS/FUV ACCUM 52X0.5 G140L 1425 1 418 S POS TARG 0, 1; PATTERN 2 -MAMA (1672 S) 5 ------------------------------------------------------------------------------------------------------------------------------------ 6 B2V-3 STIS/FUV ACCUM 52X0.5 G140L 1425 1 418 S POS TARG 0, 3; PATTERN 2 -MAMA (1672 S) 6 ------------------------------------------------------------------------------------------------------------------------------------ Sub Exposures ------------------------------------------------------------------------------------------------------------------------------------ Target | Exp |Instr | Oper. | Aper |Spectral|Cent.|Primary |Secondary |Iteration |CR-SPLIT |Orbit |Duration Name | Num |Config | Mode | or FOV |Element |Wave.|Pattern Pos |Pattern Pos |Num |Num |Number | ------------------------------------------------------------------------------------------------------------------------------------ O3V 1 STIS/CCD ACQ F28X50LP MIRROR none none none none 1 N/A O3V 2 STIS/CCD ACQ/PEA 52X0.1 MIRROR none none none none 1 N/A K O9V-3.B2.5V 3 STIS/FUV ACCUM 52X0.5 G140L 1425 1 none none none 1 N/A -MAMA O9V-3.B2.5V 3 STIS/FUV ACCUM 52X0.5 G140L 1425 2 none none none 1 N/A -MAMA O9V-3.B2.5V 3 STIS/FUV ACCUM 52X0.5 G140L 1425 3 none none none 1 N/A -MAMA O9V-3.B2.5V 3 STIS/FUV ACCUM 52X0.5 G140L 1425 4 none none none 1 N/A -MAMA B2V-1 4 STIS/FUV ACCUM 52X0.5 G140L 1425 1 none none none 2 N/A -MAMA 17223( 3) - 09-Jun-2023 12:33:20 - [ 8] Sub Exposures ------------------------------------------------------------------------------------------------------------------------------------ Target | Exp |Instr | Oper. | Aper |Spectral|Cent.|Primary |Secondary |Iteration |CR-SPLIT |Orbit |Duration Name | Num |Config | Mode | or FOV |Element |Wave.|Pattern Pos |Pattern Pos |Num |Num |Number | ------------------------------------------------------------------------------------------------------------------------------------ B2V-1 4 STIS/FUV ACCUM 52X0.5 G140L 1425 2 none none none 2 N/A -MAMA B2V-1 4 STIS/FUV ACCUM 52X0.5 G140L 1425 3 none none none 2 N/A -MAMA B2V-1 4 STIS/FUV ACCUM 52X0.5 G140L 1425 4 none none none 2 N/A -MAMA B2V-2 5 STIS/FUV ACCUM 52X0.5 G140L 1425 1 none none none 2 N/A -MAMA B2V-2 5 STIS/FUV ACCUM 52X0.5 G140L 1425 2 none none none 2 N/A -MAMA B2V-2 5 STIS/FUV ACCUM 52X0.5 G140L 1425 3 none none none 3 N/A -MAMA B2V-2 5 STIS/FUV ACCUM 52X0.5 G140L 1425 4 none none none 3 N/A -MAMA B2V-3 6 STIS/FUV ACCUM 52X0.5 G140L 1425 1 none none none 3 N/A -MAMA B2V-3 6 STIS/FUV ACCUM 52X0.5 G140L 1425 2 none none none 3 N/A -MAMA B2V-3 6 STIS/FUV ACCUM 52X0.5 G140L 1425 3 none none none 3 N/A -MAMA B2V-3 6 STIS/FUV ACCUM 52X0.5 G140L 1425 4 none none none 3 N/A -MAMA 17223( 3) - 09-Jun-2023 12:33:20 - [ 9] Visit: 31 (STIS-OFFSET-C) Visit Requirements: ORIENT 285.765083D TO 285.765083 D On Hold Comments: Additional Comments: The fixed orient is necessary tp fit two stars simulatniously in one slit. This method saves more 5 orbits in total Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exp | Target | Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Num | Name | Config | Mode | or FOV |Element |Waveln.| Parameters |Exp| (Total) | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 O3V STIS/CCD ACQ F28X50LP MIRROR 1 0.2 S (0.2 S) ------------------------------------------------------------------------------------------------------------------------------------ 2 O3V STIS/CCD ACQ/PEA 52X0.1 MIRROR 1 0.2 S (0.2 K S) ------------------------------------------------------------------------------------------------------------------------------------ 3 O7V STIS/FUV ACCUM 52X0.5 G140L 1425 1 103 S (412 POS TARG 0, 3; PATTERN 2 -MAMA S) 3 Comments: The ETC Run # for the other star in the slit is: STIS.sp.1331332716 The combined global count rate is: 11421 far below the safety limits. ------------------------------------------------------------------------------------------------------------------------------------ 4 O8.5V.O9V-1 STIS/FUV ACCUM 52X0.5 G140L 1425 1 295 S POS TARG 0, 3; PATTERN 2 -MAMA (1180 S) 4 Comments: The other potential sources in the slit are: O8.5V_a (F555W=15.209): STIS.sp.1864812, 3449 O8.5V_b (F555W=15.645): STIS.sp.1864811, 2308 O9V-3 (F555W=15.543): STIS.sp.1864810, 2535 The total possible countrate is 11021 well below the safty limit ------------------------------------------------------------------------------------------------------------------------------------ Sub Exposures ------------------------------------------------------------------------------------------------------------------------------------ Target | Exp |Instr | Oper. | Aper |Spectral|Cent.|Primary |Secondary |Iteration |CR-SPLIT |Orbit |Duration Name | Num |Config | Mode | or FOV |Element |Wave.|Pattern Pos |Pattern Pos |Num |Num |Number | ------------------------------------------------------------------------------------------------------------------------------------ O3V 1 STIS/CCD ACQ F28X50LP MIRROR none none none none 1 N/A O3V 2 STIS/CCD ACQ/PEA 52X0.1 MIRROR none none none none 1 N/A K O7V 3 STIS/FUV ACCUM 52X0.5 G140L 1425 1 none none none 1 N/A -MAMA O7V 3 STIS/FUV ACCUM 52X0.5 G140L 1425 2 none none none 1 N/A -MAMA O7V 3 STIS/FUV ACCUM 52X0.5 G140L 1425 3 none none none 1 N/A -MAMA O7V 3 STIS/FUV ACCUM 52X0.5 G140L 1425 4 none none none 1 N/A -MAMA O8.5V.O9V-1 4 STIS/FUV ACCUM 52X0.5 G140L 1425 1 none none none 1 N/A -MAMA 17223( 3) - 09-Jun-2023 12:33:20 - [ 10] Sub Exposures ------------------------------------------------------------------------------------------------------------------------------------ Target | Exp |Instr | Oper. | Aper |Spectral|Cent.|Primary |Secondary |Iteration |CR-SPLIT |Orbit |Duration Name | Num |Config | Mode | or FOV |Element |Wave.|Pattern Pos |Pattern Pos |Num |Num |Number | ------------------------------------------------------------------------------------------------------------------------------------ O8.5V.O9V-1 4 STIS/FUV ACCUM 52X0.5 G140L 1425 2 none none none 1 N/A -MAMA O8.5V.O9V-1 4 STIS/FUV ACCUM 52X0.5 G140L 1425 3 none none none 1 N/A -MAMA O8.5V.O9V-1 4 STIS/FUV ACCUM 52X0.5 G140L 1425 4 none none none 1 N/A -MAMA 17223( 3) - 09-Jun-2023 12:33:20 - [ 11] Summary Form for Proposal 17223 Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Apertures 52X0.1, 52X0.5, F28X50LP ------------------------------------------------------------------------------------------------------------------------------------ Configurations STIS/CCD, STIS/FUV-MAMA ------------------------------------------------------------------------------------------------------------------------------------ Opmodes ACCUM, ACQ, ACQ/PEAK ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements ORIENT 285.765083D TO 285.765083 D, ORIENT 315.189547D TO 315.189547 D, ORIENT 340.089743D TO 340.089743 D, PATTERN 2 3, PATTERN 2 4, PATTERN 2 5, PATTERN 2 6, POS TARG 0, -2, POS TARG 0, 1, POS TARG 0, 3, POS TARG 0, 5 ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements G140L, MIRROR ------------------------------------------------------------------------------------------------------------------------------------ Target Names B1.5IV-E, B2V-1, B2V-2, B2V-3, O3V, O7V, O8.5V.O9V-1, O9V-2.B0.7V, O9V-3.B2.5V ------------------------------------------------------------------------------------------------------------------------------------