Figure 1 from Whitaker et al. (2011): A region of the COSMOS field (roughly 2' on a side), shown for a broadband J-filter (left) and a three color image from the medium-band J1, J2, J3 filters (right). The red object in the bottom left of the image highlights the spectral features that we are able to resolve within only 0.2μm in wavelength (see inset SED). The J-filters trace out the Balmer/4000A break with higher resolution than the standard broadband filter, allowing for an accurate photometric redshift of this quiescent galaxy at z=2.02. The normalized transmission curves of the filters in the NMBS catalogs are shown in the top panel; the medium-bandwidth filters are red and the additional COSMOS filters (e.g. the Subaru optical medium-band filters) are shown in grey-scale behind the five CFHT optical filters.
The NEWFIRM Medium-Band Survey (NMBS) used the NOAO Extremely Wide-Field Infrared Imager (NEWFIRM) on the KPNO Mayall 4 m Telescope to obtain deep near-IR (NIR) medium-bandwidth photometry over the wavelength range 1-1.8 μm + K-band in the All-wavelength Extended Groth strip International Survey (AEGIS) and Cosmic Evolution Survey (COSMOS) fields. The NMBS team (Whitaker at al. 2011) computes photometric redshifts for objects in the fields using 37 (20) filters in the COSMOS (AEGIS) fields, combining the NIR medium-bandwidth data with existing UV (Galaxy Evolution Explorer), visible and NIR (Canada-France-Hawaii Telescope and Subaru Telescope), and mid-IR (Spitzer/IRAC) imaging. They find excellent agreement with publicly available spectroscopic redshifts, with σz/(1 + z) ~ 1%-2% for ~ 4000 galaxies at z = 0-3. The NMBS catalogs contain ~13,000 galaxies at z > 1.5 with accurate photometric redshifts and rest-frame colors. Due to the increased spectral resolution obtained with the five NIR medium-band filters, the median 68% confidence intervals of the photometric redshifts of both quiescent and star-forming galaxies are a factor of about two times smaller when comparing catalogs with medium-band NIR photometry to NIR broadband photometry.
NMBS at a Glance
|PI(s)||Pieter van Dokkum|
|Years of Observation||2008-2009|
|Area covered:||Deep NIR imaging of the AEGIS and COSMOS fields|
|Bands||J1, J2, J3, H1, H2, K|
|AEGIS Depth (5σ)||(J1, J2, J3, H1, H2, K) = (21.9, 22.0, 21.3, 21.1, 21.4, 21.5)|
|COSMOS Depth (5σ)||(J1, J2, J3, H1, H2, K) = (21.7, 21.5, 21.4, 21.3, 20.9, 21.5)|
|AEGIS Seeing||(J1, J2, J3, H1, H2, K) = (1.1, 1.2, 1.1, 1.1, 1.1, 1.1) arcsec|
|COSMOS Seeing||(J1, J2, J3, H1, H2, K) = (1.2, 1.2, 1.1, 1.0, 1.2, 1.1) arcsec|
|Number of images||12 Deep stacks (6 filters in 2 fields)|
- More information: Archive of NMBS website
- Survey publication: http://adsabs.harvard.edu/abs/2011ApJ...735...86W
- Data Release [FTP link]
- NOAO Science Data Archive search form. The default search will return the full survey holdings. Use the options on the form, or the returned listing of data products to refine the search further.