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James Webb Space Telescope
Science Operations Design Reference Mission

JWST SODRM Distant Galaxies Programs Summary

TITLE: JWST Ultra-Wide NIRCam and MIRI Mosaic of the Extended Groth Strip

ID: 95010

GOAL: Wide field NIRCam (F200W/F356W) and MIRI (F1500W) for statistical extra-galactic studies; rest-frame optical and IR structures and high-spatial resolution spectral energy distributions for 1 < z < 8 galaxies to study galaxy assembly, star-formation histories, AGN host galaxy properties, and faint/low mass galaxy populations during the first half of the universe's lifetime. This program will reach point source depths of ~29 ABmag in K, ~26.5 ABmag in F356W, and 24 ABmag in F1500W. The large area and sample obtained by ultra-wide field (~0.5 deg x 0.5 deg) allows for studies of rare objects and for understanding the effects of cosmic variance.

NOMINAL ALLOCATION (hours):

500

TARGET(S ):

Extended Groth Strip ( ~0.5 deg x 0.5 deg FOV)

OBSERVING TEMPLATE:

NIRCam imaging
MIRI Imaging

OBSERVATION DETAILS:

NIRCam 10 x 9 Mod A+B mosaic
MIRI 15 x 14 mosaic

  1. NIRCAM:
    Modules A + B Full array
    SWC: F200W
    LWC: F356W
    Dither pattern: FULL
    3 primary dithers, no secondary dithers
    Exposures: DEEP8
    5 groups
    932.8 s exp per dither
    position = 2798.4 per pointing x 90 pointings
    (10 x 9 mosaic) = 70.0 hours NIRCam science integration time.
  2. MIRI:
    FULL array
    Filter: F1500W
    Dither pattern: Cycling
    5 point,s
    MEDIUM pattern size
    no secondary dithers
    Exposures: SLOW
    37 groups
    1002.885 s exp per dither position = 5014.4 per pointing x 210 pointings
    ( 15x14 mosaic) = 292.5 hrs MIRI science integration time
  3. Total science integration time = 362.5 hrs

CONSTRAINTS:

Given NIRCam's rectangular shape, 'same as' orient constraints for all NIRCam mosaic pointings. No such constraints given for MIRI mosaic pointings, although gaps between mosaic tiles are undesirable.

PARALLEL Observations possible (yes/no/pure parallel)?

Yes -- parallel NIRSpec observations for wide-field spectroscopy; NIRSS parallel imaging would make the program 1/3 more efficient.

PROGRAM COORDINATOR/DATE: J. Lotz/Dec 22, 2011

TITLE: JWST NIRCam and MIRI Mosaic of the Chandra Deep Field South

ID: 95020

GOAL: To obtain deep and 'wide' NIRCam multi-band, multi-epoch mosaic of well-studied extra-galactic ti-band, multi-epoch mosaic of well-studied extra-galactic field; to detect z~8-10 galaxies, measure high redshift galaxy properties (luminosities, star-formation rates, structures), and detect high redshift transients. Deep MIRI imaging in F2100W will measure spatially-resolved mid-IR luminosities and SFR ~five times deeper than current Spitzer 24 micron imaging, with 5-sigma limiting SFRs ~ 1, 5 Msun/yr at z~1, 2 respectively.

NOMINAL ALLOCATION (hours):

400

TARGET(S ):

Chandra Deep Field South, ~ 10" x 16" FOV

OBSERVING TEMPLATE:

NIRCam imaging
MIRI imaging

OBSERVATION DETAILS:

  1. NIRCam: Number of pointings/targets/epochs: 12 pointings for 1 cluster target for 10 epochs
    Cluster Target: Yes
    Modules A + B Full array
    SWC: F090W 30 ks per pointing (total) F115W 15 ks
    F150W 15 ks
    LWC: F444W 30 ks (total) F227W 15 ks
    F356W 15 ks
    Dither pattern: FULL, 3 primary dithers, no secondary dithers
    Exposures: F090W/F444W, DEEP8, 6 groups, 1144.8s exp per dither position for 3434.4 s per pointing
    F115W/F277W, DEEP8, 3 groups, 508.8s exp per dither position for 1526.4s per pointing
    F150W/F356W, DEEP8, 3 groups, 508.8s exp per dither position for 1526.4s per pointing
    x 12 pointings x 10 epochs = 217 hours NIRCam science integration time.

  2. MIRI: Number of pointings/epochs: 56 pointings for 1 cluster target for 1 epoch
    Cluster Target: Yes
    MIRI imaging, FULL array, FILTER= F2100W
    Dither pattern: CYCLING, 10 pts, MEDIUM
    Readout pattern: SLOW, 37 groups, 1 integration, 1002.885 exp. time per dither for total exposure per pointing ~ 10,029 s
    x 56 = 156 hours MIRI science integration time

Overlapping NIRCam 10 x 9 pointing mosaic and MIRI 15 x 14 mosaic (center) planned by APT. MIRI exposures are much more expensive, hence only cover the high-coverage regions of the NIRCam mosaic.

CONSTRAINTS:

Orient constraints within each epoch to maintain a uniform mosaic. Given the rectangular nature of NIRCam FOV, unique mosaic patterns for each orient/epoch would be preferred to give best overlap of different epochs Required all observations at given epoch performed within 15 days.

Timing constraints with 30-50 day cadence between epochs for optimal high-z SNe search. No constraints on MIRI observations.

PARALLEL Observations possible (yes/no/pure parallel)?

Yes -- parallel NIRSpec observations for wide-field spectroscopy; NIRSS parallel imaging would make the program 1/3 pectroscopy; NIRSS parallel imaging would make the program 1/3 more efficient.

PROGRAM COORDINATOR/DATE: J. Lotz/Jan 13, 2012

TITLE: JWST Ultra Deep Field Imaging Survey

ID: 95030

GOAL: The primary purpose of this program is to search for first light objects, allowing the identification of the sources of reionization and the study the evolution of the star formation rate of the Universe from first light to reionization. This program aims to reach depths in the range AB~31-31.5 in the F090W, F110W, F150W, F200W, F227W,F356W, and F444W NIRCam filters, along with MIRI F560W and F777W, with a goal of probing the z ~ 10 - 15 universe to measure the physical properties of the highest redshift galaxies and star-forming regions.

Sample and sky coverage will be a single field, proposed to be the Hubble UDF. Because of 90 degrees orient changes one of the two cameras will be on the same field for the entire program, the second camera will observe 2 displaced fields. The program remains feasible even without a constraint on the orient changes different angle would change the fraction of area covered as a function of depth. The MIRI field is unconstrained as the field of view of MIRI is fully contained within one NIRCam camera.

NOMINAL ALLOCATION (hours):

600

TARGET(S):

HST UDF (03 32 -27 40)

OBSERVING TEMPLATES:

NIRCam Imaging
MIRI Imaging

OBSERVATION DETAILS:

The NIRCam observations are divided into a total of 20 observations, each one at a different pointing center from the Intra-SCA medium dither pattern sequence. Each of these observations will consist of a 4-point secondary dither pattern, and at each of these 4 points there will be 4 exposures, in the 4 SW filters (along with 3 LW filters in a 1:1:2 ratio). The total integration time per filter at each dither pointing is 3264.8 sec (and 4 integrations, one for each SW and LW filter in parallel, are obtained at each of the 4 secondary dither pointings).

The MIRI observations are also obtained at 20 different pointing centers, with each observation utilizing a 16-point Reuleaux pattern as a secondary dither pattern. At each of these 16 points, 2 exposures will be obtained, one each for F560W and F777W, in SLOW mode, 34 groups, FULL array. The total integration time per filter at each dither pointing is 921.57 sec (and 2 filters are obtained at each of the 16 secondary dither pointings).

CONSTRAINTS:

For the NIRCam observations, the field needs to be revisited at least 4 times with 90 degree orientations. Each of these epochs will consist of 5 observations. Supernovae will be searched at each epoch. For the 4 epochs option each set of visits at the same orient lasts 100 hrs.

There is no constraint on the MIRI observations.

PARALLEL Observations possible (yes/no/pure parallel)?

Taking parallel NIRCam/MIRI Imaging while the other was prime would be highly advantageous for constructing multiple parallel deep fields.

PROGRAM COORDINATOR/DATE: A. Koekemoer/2 Dec 2011

TITLE: JWST Wide-Area Spectroscopic Followup

ID: 95040

GOAL:

This goal of this program is to measure redshifts continuum SEDs and emission-line strengths for galaxies in JWST wider-area surveys. This will help to constrain the evolution of galaxies, the masses of their dark-matter halos (via clustering), the evolution of AGN, and the buildup of dust and metals, all of which are core goals of JWST. As a fiducial goal, we will adopt S/N = 10 in the continuum for AB=26.0 for a flat-spectrum source for low-resolution prism spectra, and a flux limit of 5x10-18 erg cm-2  s-1 for emission-lines near the prism bandpass. The continuum limit corresponds to an unobscured star-formation rate of 86 at z=6.

Features of interest at redshifts include the rest-UV & optical continuum and various diagnostic lines, Lya l1216, He II l1640, [O III] l5007, Ha, Hb, [Ne V] l1575,3426, [Ne IV] l1602,2423, OIII] l1663, and [OII] l2471,3727, NV 1240, Si II 1309, CII 1335, CIV 1550, CIII] 1909, and a variety of others (e.g. Humphrey et al. 2008, MNRAS, 383, 11; Inoue 2011, MNRAS, 415, 2920).

According to the prototype ETC for the prism, for a source with AB=26 at (2,3.5) mm one could get S/N = (19,10) per resel in 3 hours. According to the prism sensitivity tables on the web, the 10s limiting emission-line flux limits in 3 hours at 2,3.6 mm are 22,9.0 x 10-1 erg cm-2  s-1.

NOMINAL ALLOCATION (hours):

400

TARGET(S):

CANDELS fields
Field RADecTiling pattern
GOODS-S03:32:30-27:48:20 11x7
GOODS-N12:36:55+62:14:15 7x11
EGS14:17:00+52:30:00 6x17
UDS02:17:49-05:12:02 4x13
COSMOS10:00:28+02:12:21 4x13
The details of the tiling patterns depend on the orientation.

OBSERVING TEMPLATE:

NIRSPec MulitObject Spectroscopy

OBSERVATION DETAILS:

For this strawman program, we observe only with the prism at R=100, since the goal is to sample a large volume. The density of galaxies at AB=26 is about 100 per square arcminute. If we take the 171 slits in the spatial direction and assume we have one galaxy every 5 slits, on average, along the spatial direction, and that we are able to fit three sources per row on average without overlapping the spectra in the dispersion direction, then we can achieve 103 galaxies per square arcminute.

We assume we have NIRCam images to identify candidates, and will do the target acquisition using brighter sources in the F110W l do the target acquisition using brighter sources in the F110W target-acquisition filter.

The fields will be observed in overlapping tiles, such that most of the sources are observed in three different tiles. If we adopt a fiducial 1 hour per tile, then most sources get 3 hours of observations, and sources near the border of the mosaic mostly get 2 hours, with just the corners getting 1 hour. Tiles that overlap by 50-60% accomplish this. Because each source ends up with 2-3 very different slitlets, we simply add a single nod on top of that. So each tile gets exposed twice for about 1800s each time, with a nod in between the exposures.

Mode

Total hours

NTSET

NSLITLET

NNOD

WAVEGAP

Prism

3

1

1

2

NO

CONSTRAINTS:

The fields can be mosaiced at any orientation, but some orientations are a bit more efficient than others. Having picked an orientation, it is best to do the entire field at that orientation.

PARALLEL Observations possible (yes/no/pure parallel)?

While some of the science goals could be accomplished with a NIRspec pure parallel program, obtaining a target list and assigning slits would be challenging.

PROGRAM COORDINATOR/DATE: H. Ferguson

TITLE: Grism Spectra of Deep Fields

ID: 95050

GOAL:

The primary goal of this program is to search for galaxies at redshifts z>7 with strong emission lines of Lyman-a HeII 1640. The main benefit of slitless spectroscopy for this program is that it enables a truly blind search for such galaxies. Early star-forming galaxies, before forming significant amounts of dust, may have extremely large Lyman- a equivalent widths (albeit scattered by the IGM), and hence may be difficult to detect in the continuum. Very metal-poor galaxies expected to be very strong in He II 1640 A. Some Lya predictions are provided by Stark et al. 2007, ApJ, 668, 627.

To get a rough idea of exposure times, Lya redshift ranges and number of sources per sq. arcmin for h,W, Wm, Wl = 0.7,1,0.73,0.27 are given for a fiducial number density of 10-3 Mpc-3. Fluxes corresponding to a Lya luminsity of 1042 erg s-1 are provided, and compared to the emission-line sensitivity limits for 10ks, 10s (read from the plot on the NIRISS web page, and taken from Greene et al. 2007 SPIE for NIRCAM).

Mode z N arcmin-2
for
n=10-3Mpc-3
Flux limit
(10-18 erg s-1 cm2 )
Flux
corresponding
to 1042 erg s-1
NIRISS F115W 7.2-9.6 5.1 7-15 1.2
F140M 9.9-11.2 2.3 5 0.64
F158M 11.3-13 2.6 5 0.47
F150W 9.9-12.8 4.7 7 0.54
F200W 13.4-17.3 4.7 6 0.27
NIRCAM F250M18.9-20.21.350.16
F300M 22.4-24.9 1.8 5 0.11
F335M 25.2-27.9 1.8 5 0.08
F360M 27.1-30.1 1.8 5 0.07
F410M 31-34.4 1.7 5 0.05

Exposure times for these fiducial numbers range from very long to hopeless. For example, reaching 10s at 1042 erg s-1 in F140M would take about 170 hours. The trade between observing with F150W to cover the full range z=10-13 versus splitting the range with F140M and F158M looks like a bit of a wash. However, if one suspects that the lower part of the redshift range is where the detectable sources will be, then concentrating on F140M probably wins.

NOMINAL ALLOCATION (hours):

200

TARGET(S):

OBSERVING TEMPLATE:

NIRISS WFSS
NIRCam Grism

OBSERVATION DETAILS:

We put most of the time into NIRISS F140M because it is likely to yield the most sources. We do a shallow survey at other wavelengths in case there are sources much brighter than expected from the models.
NIRISS F140M - 100 hours
NIRISS F158M - 30 hours
NIRISS F200W - 40 hours
NIRCAM F250M - 30 hours

The F200W and F250M observations will primarily help with interloper rejection, finding the H associated with [OIII] emitters in the shorter filters.

We split the time 50/50 between the two grisms (counter-dispersed in NIRISS, cross-dispersed in NIRCam). We also rotate 10 degrees to break degeneracies in extracting sources. We dither in a small pattern because we do not care about filling gaps between detectors.

CONSTRAINTS:

The exact orientation is probably not terribly important. Being able to obtain 2 frames with about 10 degrees difference in orientation helps with deblending the spectra.

PARALLEL Observations possible (yes/no/pure parallel)?

The whole program could in principle be done as a parallel program deep imaging programs. In fact, it is extremely interesting as a parallel program because the depth*area constraints needed for interesting constraints on the Lya luminosity function verge on prohibitive for a prime program.

PROGRAM COORDINATOR/DATE: H. Ferguson

TITLE: JWST Ultra-Deep Spectroscopy

ID: 95060

GOAL:

The primary goal of this program is to confirm candidates for very high-redshift galaxies and look for spectral signatures of young, extremely-metal-poor stellar populations. We assume the candidates have been selected from NIRCam and/or NIRISS programs and have a range of brightness, but that there are a small number that will want the full exposure time. Features of interest include the rest-UV & optical continuum and various diagnostic lines, Lya l1216, He II l1640, [O III] l5007, Ha, Hb, [Ne V] l1575,3426, [Ne IV] l1602,2423, OIII] l1663, and [OII] l2471,3727, NV 1240, Si II 1309, CII 1335, CIV 1550, CIII] 1909, and a variety of others (e.g. Humprhey et al. 2008, MNRAS, 383, 11; Inoue 2011, MNRAS, 415, 2920). A variety of papers have made flux predictions, which at high-redshifts tend to be challenging even for the deepest NIRSpec exposures (e.g. Johnson 2011; astroph1105.5701). Half-light radii are expected to be 0.05-0.1 arcsec for z>6 (Wyithe & Loeb 2011, MNRAS, 413, L38).

Consider sources at z=10,15,20 with flat-spectrum AB magnitude 29. (This corresponds to unobscured star-formation rates of rates of ~18,44,84 solar masses per year). According to the prototype ETC for the prism, for a source with AB=29 at (1.3,2,2.6) mm one could get S/N = (10,8,7) per resel in 100 hours. Scaling the the sensitivity tables on the web by t-0.5 , 10s limiting emission-line fluxes in 100 hours at 1.3,2,2.6 mm are 4.1,2.4,1.9 x 10-19 erg  cm-2 s-1.

NOMINAL ALLOCATION (hours):

400

TARGET(S):

HST Ultra-Deep Field

OBSERVING TEMPLATE:

NIRSPec MulitObject Spectroscopy

OBSERVATION DETAILS:

For this strawman program, we observe both with the prism at R=100 and with the G140M, G235M, and G395M gratings at at R=1000 (all grating settings). The R=100 setting will be most useful for measuring the continuum and spectral breaks. The R=1000 setting will be more sensitive for emission lines. The most important lines are probably Lya, He II, and [O III]. Because [OIII] is beyond the NIRSpec wavelength range for z>9, and HeII is in the G235M range for z<17, we invest less time in G395M.

We assume we have NIRCam images to identify candidates, and will do the target acquisition using brighter sources in the F110W target-acquisition filter. Assume that we have ~20 targets scattered around the field that desire maximum depth, and a wedding-cake of brighter sources that can be placed on slits for shorter amounts of time. We would probably optimize the pointing centers to put the best high-z candidates in the sweet-spot of the apertures.

For faint objects, sky subtraction will be the limiting factor. The strategy here combines ''nodding'' along a slitlet with larger moves to help remove detector systematics. The faintest targets would

Mode Total hours NTSET NSLITLET NNOD WAVEGAP
Prism 100 10 5 2 NO
G140M 125 8 3 2 YES
G235M 125 8 3 2 YES
G395M 50 4 2 2 YES

CONSTRAINTS:

Probably one will want to constrain the orientation to optimize the coverage with NIRCAM, but this would allow 4 possible orientations with windows of at least 10 degrees around each. Having started in one observing mode (e.g. prism), one will probably want to complete the observations with the same orientation. However, the limited amount of time available at one orientation may force the observations to be broken up.

PARALLEL Observations possible (yes/no/pure parallel)?

Parallel imaging with the other instruments would be possible.

An obvious thing to consider would be to designate two deep fields such that one could do imaging on one in parallel with spectroscopy on the other; then come back in 6 months and swap the imaging and spectroscopy.

PROGRAM COORDINATOR/DATE: H. Ferguson

TITLE: MIRI LRS spectra of distant galaxies

ID: 95070

GOAL:

This program serves as a catch-all for MIRI low-resolution spectroscopy of high-redshift galaxies (z>2). There are a wide variety of science goals, including (1) constraining star- formation rates, dust, extinction and metallicity during the epoch of reionization at z>7 using strong features such as Ha, [OIII], and the 4000 Angstrom break. (2) Measuring the chemical evolution of galaxies and the incidence of AGN over a broad range of redshift using a wide variety of spectral diagnostics such as Paschen and Brackett lines, H2 and CO features, [SIII], [OIII], [FeII], Ne VI, and the Calcium triplet. (3) Measuring the evolution of hot dust through PAH features such as those at 6.2, 7.7 and 8.6, and 11.3 μm.

We assume that all of the sources in this program have been previously identified by other surveys and have high-resolution shorter-wavelength images. Sources for this program include:

  • ''Main-sequence'' star-forming galaxies at z ~ 13, 8, 4, 2 (lensed and unlensed)
  • Sub-mm galaxies at z~4,2 (lensed and unlensed)
  • Passive galaxies (& candidate passive galaxies) at z~5, 2

NOMINAL ALLOCATION (hours):

100

TARGET(S):

Target type # examples Typical Exptime (ks) Features of interest Comments, reference
z~13 Main-seq 2 50,10 [OIII], Ha, 4000A break e.g. Source J1 in Laporte et al. 2011
z~8 Main-seq 2 25 Ha Yan et al. 2001, Oesch et al. 2012
z~4 Main-seq 5 10 Rest-K continuum Lee et al. 2004, Ouchi et al. 2004
z~2 Main-seq 5 5 Brb,g, CO 2.3mm, H2
1-0, PAH 3.3 mm
Reddy et al. 2005
z~4 sub-mm 5 10 Rest-K continuum Daddi et al. 2009, Knudsen et al. 2006
z~2 sub-mm 5 5 Brb,g, CO 2.3mm, H2
1-0, PAH 3.3 mm
Lapi et al. 2011, Ashby et al. 2006, Pope et al. 2006
z~5 passive 5 5 Ca triplet, Pa series Wiklind et al. 2008
z~2 passive 5 10 Brb,g, CO 2.3mm, H2
1-0, PAH 3.3 mm
Reddy et al. 2006

OBSERVING TEMPLATE:

MIRI Low Resolution Spectroscopy

OBSERVATION DETAILS:

For some of these sources it is likely that target acquisition from a brighter reference target will be preferred, to save time. MIRI (or NIRCam) pre-imaging would be required to select the reference sources. We have put in some MIRI images to serve as placeholders for this, although it is quite likely that most such sources would be identified from separate imaging programs

CONSTRAINTS:

None.

PARALLEL Observations possible (yes/no/pure parallel)?

These are pointed observations, so can't really be done in parallel with other observations. They are long pointings, often in favorite parts of the sky, so parallel observations with other instruments would be desirable.

PROGRAM COORDINATOR/DATE: H. Ferguson

TITLE: Confirmation, photo-z's and Physical Properties of SZ-selected Galaxy Clusters

ID: 95080

GOAL:

Galaxy clusters are a powerful probe of the structure growth in the Universe. Currently, several projects use the SZ-effect to detect the most massive galaxy clusters candidates in a blind, redshift-independent search. With these NIRcam observations, we confirm 500 SPT cluster candidates in a 2005 deg2 field, determine their photo-z, and use their physical properties to constrain galaxy evolution and structure growth.

NOMINAL ALLOCATION (hours):

200

TARGET(S):

500 SPT cluster candidates.

OBSERVATION DETAILS:

8x53 second exposures in each F356W and F444W with LWC, SWC is bonus. RAPID readout, 5 groups, 1 integration is 53 seconds. Small dithers fill out the intrasca chip gaps, 4 large dithers optimize deep in the core (300 sec effective exposure time) and shallower outside (see observing scenario). The area covered is a circle with a diameter of 5', deeper at the core (diameter of ~1.5').

CONSTRAINTS:

The 1.14h per target is dominated by slew time (~45%), and re-aquisition of guide stars (30%), leading to an efficiency of ~25%. Since the density of targets is 1 cluster per 5 square degree, typical slews are only a couple of degrees, and the slew time is probably much less if planned wisely. The dithers should be on the order of 1.5', so with a good plan of the dithering the aquisition of guide stars can also be minimized.

PARALLEL Observations possible (yes/no/pure parallel)?

no

PROGRAM COORDINATOR/DATE: A. Rest/Dec 12, 2012

TITLE: MIRI MRS spectra of distant galaxies

ID: 95090

GOAL:

This program serves as a catch-all for MIRI MRS spectroscopy of high-redshift galaxies (z>2). Compared to the LRS program, the observations provide detailed line strengths and line widths, spatial mapping, and kinematics. Science goals include constraining star-formation rates, dust evolution, kinematics, ISM energetics (inflows and outflows), and the chemical evolution of galaxies over a broad range of redshifts. Features of interest include redshifted Ha, the Paschen and Brackett lines, H2 and CO features, [SIII], [OIII], [FeII], Ne VI, [Ar II] and the Calcium triplet. Evolution of hot dust will be constrained using PAH features such as those at 6.2, 7.7 and 8.6, and 11.3 μm.

We assume that all of the sources in this program have been previously identified by other surveys and have high-resolution shorter-wavelength images. Sources for this program include:

  • ''Main-sequence'' star-forming galaxies at z ~ 13, 4, 2 (lensed and unlensed)
  • Sub-mm galaxies at z~4,2 (lensed and unlensed)
  • Passive galaxies (& candidate passive galaxies) at z~5, 2

NOMINAL ALLOCATION (hours):

100

TARGET(S):

Target type # examples Typical Exptime (ks) Features of interest Comments, reference
z~13 main seq 1 25 Ha Probably would need a lensed source
z~8 Main-seq 2 10 Ha Yan et al. 2001, Oesch et al. 2012
z~4 Main-seq 5 10 Rest-K continuum, Pa, Br series, CO 2.3mm, H2
1-0, PAH 3.3 mm
Lee et al. 2004, Ouchi et al. 2004
z~2 Main-seq 5 10 Br series, CO 2.3mm, H2
1-0, PAH 3.3 mm
Reddy et al. 2005
z~4 sub-mm 4 10 Rest-K continuum, Pa, Br series, CO 2.3mm, H2
1-0, PAH 3.3 mm
Daddi et al. 2009, Knudsen et al. 2006
z~2 sub-mm 5 10 Br series, CO 2.3mm, H2
1-0, PAH 3.3 mm
Lapi et al. 2011, Ashby et al. 2006, Pope et al. 2006
z~5 passive 2 20 Ca triplet, Pa series Wiklind et al. 2008
z~2 passive 2 15 Br series, CO 2.3mm, H2
1-0, PAH 3.3 mm
Reddy et al. 2006

OBSERVING TEMPLATE:a

MIRI Medium Resolution Spectroscopy
MIRI Imaging

OBSERVATION DETAILS:

Exposure times are very rough guesses, probably tending to be on the optimistic side. A galaxy with an unobscured star-formation rate of 100 solar masses per year at z=8 will have Ha = 1.5x10-20W m-2, which is within range in 10ks, but the known sources at z=8 have lower inferred star-formation rates from their rest UV. Similar calculations suggest long exposure times for z=4 UV main-sequence sources in Paschen a. On the other hand, detecting the 3.3 micron PAH feature in bright sub-mm galaxies should be pretty easy.

For a few of these sources it is likely that target acquisition from a brighter reference target will be preferred, to from a brighter reference target will be preferred, to save time. MIRI (or NIRCam) pre-imaging would be required to select the reference sources. These sources are all small enough to fit into the MRS field of view. Given the long exposure times, one presumably use a small dither pattern to improve spatial sampling.

Different channels will be of interest for different redshift ranges.

It is difficult at this stage to know whether investigators will tend to choose one grating setting (e.g. to go after a specific line) versus all of the settings to get several lines or the continuum. Many of these sources will probably be undetectable in continuum in the MRS. Some will probably have redshifts prior to the observations (e.g. from ALMA), but others won't. For this SODRM program, we have selected one grating setting on a few sources, and all three settings for most of them.

CONSTRAINTS:

None.

PARALLEL Observations possible (yes/no/pure parallel)?

These are pointed observations, so can not really be done in parallel with other observations. They are long pointings, often in favorite parts of the sky, so parallel observations with other instruments would be desirable.

Parallel imaging with the MIRI imager (if it were possible) would of course save having to take a separate reference image for each dither position.

PROGRAM COORDINATOR/DATE: H. Ferguson

TITLE: MIRI Observations of High-Redshift Active Galactic Nuclei

ID: 95100

GOAL:

This program aims to probe the relationship between AGN fuelling and galaxy mergers, by observing a sample of extremely IR-luminous galaxies at the peak of cosmic star formation and AGN activity (z~2-3). In models of galaxy / black hole co-evolution (eg Hopkins et al. 2005, 2007), mergers between galaxies can lead to substantial fuelling of heavily obscured central AGN, and in fact up to 90% of AGNs at this redshift range may be heavily obscured (e.g., Gilli et al. 2009). We must understand this population to learn the role they play in the evolution of galaxies and the integrated light of the Universe. Explorations of these source types must be concentrated in the MIRI wavelength bands because of the strong extinction. Although it has taken 30 years to gain a reasonable understanding of the mid-infrared properties of local Ultraluminous Infrared Galaxies and Type 2 AGNs, the power of JWST lets us extend many key observations all the way back to the quasar heyday at z ~ 2 - 2.5.

The hard UV / Xray fluxes from the obscured AGN can be traced from their ionizing radiation. A key line is [NeVI] at 7.65 μm rest wavelength; it is the shortest wavelength bright high excitation line, and its rest wavelength lies in a region of exceptional transparency of the interstellar medium, A(7.6 μm) < 0.02 AV. Thus, sources where the rest optical line emission is totally inaccessible can be studied with this line using MIRI up to z ~ 2.5, determining key parameters such as the true AGN hard UV energetics. Studies can be extended to even higher redshifts using the ''coronal'' high excitation lines. There are a number of strong lines of this type at 2 to 4 μm rest wavelengths (e.g., Greenhouse et al. 1993, Moorwood et al. 1997), such as the lines of [MgVIII] and [SiIX] in Figure 3. The sensitivity of the MIRI, combined with the absence of terrestrial atmospheric absorptions, can access these lines even for AGNs of modest luminosity.

NOMINAL ALLOCATION (hours):

129

The typical line fluxes for such sources, are 0.05 to 2 mJy or 19.68 to 15.68 AB magnitudes at 16 μm (from previous Spitzer observations, Charmandaris et al. 2004). A S/N of >10 is desirable to enable line strengths and ratios to be accurately determined, thus requiring 5 hours of exposure time per source

TARGET(S):

Sample and sky coverage will consist of z ~ 2-3 galaxies selected on the basis of previous photometry work by Spitzer, WFC3/IR, Herschel, ALMA, or ground based means. Sky coverage may be random on the sky. Total number of sources or pointings, 18.

OBSERVING TEMPLATES:

MIRI IFU

OBSERVATION DETAILS:

At z = 2.5, the [NeVI] line is shifted to 27 μm, therefore MIRI needs to have good spectral response up to at least this wavelengh. In order to examine all of the spectral lines simultaneously, we will need full wavelength coverage from 5-28.5 μm that the MIRI IFU provides. The observations are obtained over 18 visits, 1 visit per object (total time 5 h per visit), with the following setup

Slew to target so that is place in the sweetspot area
Image target with MIRI Imager (5.6 micron)
Offset to MIRI IFU
Expose with SHORT grating using SLOWMode (9-point dither pattern, 623s/dither)
Expose with MEDIUM grating using SLOWMode (9-point dither pattern, 623s/dither)
Expose with LONG grating using SLOWMode (9-point dither pattern, 623s/dither)

Note that all four IFU FOVs: IFU1A, 1B, 2A and 2B, are obtained simultaneously

CONSTRAINTS:

None.

PARALLEL Observations possible (yes/no/pure parallel)?

Parallel observations with NIRCam would be highly valuable in exploring their environments.

PROGRAM COORDINATOR/DATE: A. Koekemoer/Dec 2, 2011

TITLE: Lyman Alpha Forest S1earch for Reionization

ID: 95110

GOAL: To measure the Gunn-Peterson trough and history of reionization in the IGM from one high-S/N R = 1000 spectrum of the redshift Lyα transition toward a high-z QSO. An additional spectrum will be obtained at R = 100 to detect the possible presence of the ''Lyman beta island'', or transmission of flux in the Lyβ region of the same spectrum, which would indicate a partially reionized IGM.

NOMINAL ALLOCATION (hours):

200

TARGET(S):

A suitably chosen high-redshift QSO (z > 6). Will likely have AB=23 in the continuum longward of redshifted Lyα. We assume AB = 27 for the absorption trough where we will search for transmission at Lyβ.

OBSERVING TEMPLATE:

NIRSpec fixed-slit spectroscopy (S200A1)

OBSERVATION DETAILS:

Will use G140M (R = 1000) and the prism (R = 100). We need the short wavelength data only. We want to map the IGM along the full sightline, so dithering over the wavelength gap is required. We will use spatial and spectral dithering to optimize S/N.

PROGRAM COORDINATOR/DATE: J. Tumlinson/November 22, 2011

TITLE: Weak and Strong Lensing of SZ-selected Galaxy Clusters

ID: 95120

GOAL: Galaxy clusters are a powerful probe of the structure growth in the Universe. Currently, several projects use the SZ-effect to detect the most massive galaxy clusters candidates in a blind, redshift-independent search. Weak and strong lensing is one of the most important mass proxies for galaxy clusters, since it is a direct measure of the gravitational potential. With these NIRcam observations, the mass for 40 clusters is determined, which can then be used to calibrate other mass proxies obtained from X-rays, optical, and CMB measurements.

NOMINAL ALLOCATION (hours):

300

TARGET(S):

40 clusters

OBSERVING TEMPLATE:

NIRCam Imaging

OBSERVATION DETAILS:

For 400 seconds exposure time, assuming galaxy template M82 at redshift 1.5, the resulting S/N=5 for F444W AB mag=27 and S/N=8.5 for F227W AB mag=27. With a 3-point dither pattern, 200 second exposure per dither, the effective exposure is 2/3*(3*200 sec)=400 sec. The size of a single 3-point dither pattern is 5'x2'. A 2x5 mosaic gives then a 10'x10' mosaic size. The 3 wide LWC filters (F277W, F356W, F444W) and 3 out of the 5 SWC filters (F070W, F115W, F200W) should suffice for photo-z's

Bright2, 10 groups, 1 integration gives exposure time of 212 seconds

PARALLEL Observations possible (yes/no/pure parallel )? No

PROGRAM COORDINATOR/DATE: A. Rest/Dec 12, 2011

TITLE: High Redshift SNe/GRB Followup - A NIRSpec TOO

ID: 95140

GOAL: Obtain high-S/N spectroscopy of z > 4 supernovae and GRB afterglows, from which the explosion energy and other properties can be inferred. These observations also enable measurements of foreground gas, both in the ISM of the host galaxy and the IGM all along the sightline. Observations for many GRBs can measure the mass-metallicity relation at high z.

NOMINAL ALLOCATION (hours):

200

TARGET(S):

TBD, pending trigger from Swift, another space-based mission, or ground-based facilities such as LLST and PanSTARRS.

OBSERVING TEMPLATE:

NIRSpec fixed-slit spectroscopy

OBSERVATION DETAILS:

Obtain R = 1000 NIRSpec spectra in all available bands (G140M, G235M, G395M). Requires peak-up target acquisition to place the target in the S1600A1 aperture (note that this is not available in APT19.4, so S200A1 is used instead).

CONSTRAINTS:

This is a target-of-opportunity observation, requiring a rapid response. Having JWST on target vation, requiring a rapid response. Having JWST on target within 24 hours of the trigger is desirable.

PARALLEL Observations possible (yes/no/pure parallel)? N/A

COMMENTS:

Since TA reference stars will not be known in advance for these TOO fields, they can be triggered only when astrometry is adequate to place the target within reach of the peakup TA method for S1600A1. Since neither S1600A1 or peakup TA are available in APT19.4, they are omitted now and should be added to this program when available.

PROGRAM COORDINATOR/DATE: J. Tumlinson/November 15, 2011

TITLE: NIRCam Imaging of z~6 QSO Host Galaxies

ID: 95150

GOAL: NIRCam imaging of 25 z~6 QSO host galaxies and their immediate environments will be obtained to determine the nature and triggering mechanisms for the first quasars. We will obtain deep rest-frame 5000A and 2800A imaging with the F356W LWC and F200W SWC at 2 orientations to measure the underlying structure of the z~6 QSO hosts in module A.

Small dither steps and multiple orientations are required for PSF subtraction of the bright QSO point source. Module B observations will be used to probe the surrounding environment of the z~6 QSOs.

NOMINAL ALLOCATION (hours):

50

TARGET(S):

25 z~6 QSOs from Fan et al. 2006, Wilcott et al. 2007, 2009, and 2010

OBSERVING TEMPLATE:

NIRCam imaging

OBSERVATION DETAILS:

25 targets, each observed at two orients ~45 degree apart.
Modules A + B, with target centered on Mod A.
Full array
SWC : F200W LWC: F356W
Dither pattern: INTRASCA, LWC, 5 points, medium dither size, 1 subpixel steps (?)
Exposures: SHALLOW4 readout mode, 7 groups, 1 integrations, 360.4s exp per dither step; 1802s total exposure time per orientation

CONSTRAINTS:

Second visit has orient offset 20-70 degrees from first visit for PSF subtraction.

PARALLEL Observations possible (yes/no/pure parallel)?

No

PROGRAM COORDINATOR/DATE: J. Lotz/11/23/2011

TITLE: The Physics of Galaxy Assembly: Spatially resolved spectroscopy of high-z galaxies

ID: 95170

GOAL:

Observations up to redshift z = 2 show that there are two modes of star formation: a "quiescent mode" with low star formation efficiency in galactic disks and a "burst mode" characterized by much shorter timescales, often associated with mergers. Recent results have shown that the former is the dominant mode of star formation at these redshifts (e.g. Rodighiero et al. 2011, ApJ 739, L4). Black hole accretion, around the same cosmic epochs, is also found to be mostly associated with secularly evolving systems (e.g. Mainieri et al. 2011, A&A 535, 80). At higher redshifts the universe is denser and consequently interactions, responsible for boosting star formation efficiency, are expected to be more frequent. However, the halo gas cold inflow rate is also expected to be higher, which is also expected to generate higher star formation rates. Understanding the galaxy evolutionary mechanisms at z>2.5 has been hampered by the fact that Ha (powerful tracer of star formation and of galaxy dynamics) is redshifted out of the atmospheric transmission K-band, making ground-based integral field spectroscopic studies limited to other nebular lines, which are more ambigous diagnostics, weaker, and more subject to dust extinction (Maiolino et al. 2008, A&A 488, 463, Gnerucci et al. 2010, A&A 528, 88). Moreover, the high background in ground-based observations, combined with the rapidly dimming surface brightness at high redshift, makes ground-based spatially resolved spectroscopy even more challenging. This is particularly true for spatially resolved continuum spectroscopic observations (crucial to constrain the distribution of stellar population), which are nearly impossible from ground, even at lower redshifts (z~1-2).

We propose to obtain NIRSpec IFU observations of about 40 star forming galaxies in the redshift range spanning from z~2 to z~6, both with and without an AGN nucleus, by also including lensed systems, with the goal of constraining the physical processes responsible for galaxy evolution in the early Universe. We will use the Ha line to study the distribution of star formation within high-z galaxies to distinguish between clumpy versus diffuse star formation. By tracing the spatially-resolved ionized gas kinematics we will determine the dynamical status of these galaxies. In particular, we will identify disks characterized by a regular rotation pattern, we will measure the disk turbulence, and we will identify merging objects or those with disturbed dynamics. By measuring the gas kinematics we will also be able to identify galactic outflows, which may trace negative feedback onto the host galaxy. By combining Ha maps, probing recent star formation, and maps of the stellar continuum features, probing older populations, we will study the spatially-resolved star formation histories of galaxies. Emission line ratios will be used to derive spatially-resolved metallicities and gradients. These will provide important constraints on the integrated history of star formation and on the role of gas inflows and outflows. In galaxies hosting AGNs the broad component of Ha will allow us to infer the Black Hole mass, the narrow Ha kinematics will allow us to infer the galaxy dynamical mass, while the continuum resolved spectrum will provide the host galaxy stellar mass. This information will allow us to investigate the evolution of the MBH -Mdyn and MBH -Mstar relation out to z~6, which will provide tight constraints on the galaxy-BH coevolutionary models.

NOMINAL ALLOCATION (hours):

300

TARGET(S):

Ten star forming galaxies at z~2; five star forming galaxies at z~3; five star forming galaxies at z~6; five lensed AGNs at 4<z<6.

OBSERVING TEMPLATE:

NIRSpec IFU

OBSERVATION DETAILS:

Depending on redshift, each target will be observed with one or two of the high resolution R=2700 gratings ( to map the main nebular optical lines) and all of them will be observed with the R=100 prism (for the continuum mapping). Integration times are 2 to 6 hours for each high resolution grating setup, depending on the source brightness, and about 1-2 hours for each prism observation. Each source fits well within the IFU FoV, therefore there is no need for mosaic.

Dither parameters per grating are 3 slitlet positions, with spatial sub-pixel offsets.

CONSTRAINTS:

None

PARALLEL Observations possible (yes/no/pure parallel)?

Possible, but not relevant for the project.

PROGRAM COORDINATOR/DATE: R. Maiolino, K. Gordon, S. Arribas, H.-W. Rix, T. Boker, P. Ferruit, C. Willott, P. Jakobsen, A. Bunker, S. Charlot, M. Franx

TITLE: Constraining cosmological parameters with a restframe NIR SN Ia Hubble diagram

ID: 95180

GOAL: Although the existence of dark energy is now well established, little is known about it and understanding its nature is one of the biggest outstanding problems of modern astrophysics. Type Ia supernovae (SNe Ia) are well suited to probe the expansion history during precisely the cosmic epoch (0<z<1) in which the Universal expansion makes a transition from deceleration to acceleration. However, for SNe Ia, we are already approaching the limit where the statistical error is of the same order as the systematic error, with host galaxy extinction one of the two most significant systematic sources. With a Hubble diagram in the restframe NIR, this systematic is nearly eliminated since the extinction in these red bands is an order of magnitudes lower than in the visual. Hubble diagram with 50 SNe Ia per year, totaling 250 SNe Ia over 5 years.

NOMINAL ALLOCATION (hours):

200

TARGET(S):

50 SN Ia

OBSERVING TEMPLATE:

NIRCam Imaging

OBSERVATION DETAILS:

We use the ETC to calculate the S/N of the SN Ia at peak for different redshifts. As input spectrum, I use the Hsiao SN Ia template at peak:
http://supernova.lbl.gov/~hsiao/uber/hsiao_template.tar.gz


z=1, H=23 Vega at peak

#filterS/N(H)exptime (s)
F115W 23.5842 100
F150W 16.4425 100
F200W 14.3047 100
F277W 12.3956 100
F356W 13.0389 150
F444W 10.3607 200
z=0.5, H=22 Vega at peak
#filterS/N(H)exptime (s)
F115W 40.0799 100
F150W 40.1238 100
F200W 32.5786 100
F277W 32.2797 100
F356W 15.6408 100

z=0.2, H=21 Vega at peak

#filterS/N(H)exptime (s)
F115W 44.3754 50
F150W 38.4119 50
F200W 28.6820 50

We always observe the SWC/LWC filter pairs: F115W+F277W, F150W+F356W, F200W+F444W, RAPID readout. At peak we need at minimum S/N=10. Thus we choose exposure times for 3 difference minimum S/N=10. Thus we choose exposure times for 3 difference redshift ranges:
z<=0.2: exposure times = 50 seconds for all filters
0.2 < z <= 0.6: exposure times = 100 seconds for all filters
0.6 < z : exposure times:


F277W=100 sec
F356W=150 sec
F444W=200 sec

In order to cover the light curve, we observe 7 epochs. Their spacing depends on the redshift. For redshift z0=0.5, we choose a spacing of dt0=4 days, with a +-1 day wiggle room. For all other redshifts, we calculate the spacing dt=dt0 * (z+1.0)/(z0+1.0) . At later phases, the spacing between the epochs can be longer, therefore we space the last three epochs by 2.5*dt.

COMMENTS:

Efficiency is completely dominated by slew time. Time-domain surveys at the time JWST is launched will produce many more SNe that can be observed with JWST, which most likely will allow to cut down the slew time by smartly selecting events in close spatial proximity.

PROGRAM COORDINATOR/DATE: A. Rest/01/05/2012