1. Commissioning of ASTECAM
New Trends in Radio Astronomy in the ALMA Era (Hakone, Japan 3−8 Dec 2012
ASTE-II
ALMA / SPICA SYNERGY TELESCOPE
Here we report on the new medium-scale plan in Japan to construct a 30 – 50 m class millimeter (mm) and sub-mm single dish telescope. The main observing frequency of the telescope is 70 to 400 GHz, which just covers main atmospheric windows in good observing sites at mm and sub-mm wavelengths such as the ALMA site. We are also aiming at observations at higher frequency up to 1 THz with the limited use of the antenna surface, e.g., under-illumination of the telescope. One of important science goals in this new telescope project is unveiling the large scale structure of the high-z universe and cosmic star formation history by spectroscopic surveys of high-z galaxies in CO and [CII] lines. With exploiting synergy with ALMA this telescope can contribute to the breadth of astronomy and astrophysics, e.g, astrochemistry, star formation in the galaxy and external galaxies, cosmology, and sub-mm VLBI.
R. Kawabe (JAO/NAOJ), K. Kohno , S. Yamamoto. Y. Tamura, T. Totani (U. Tokyo), T. Kitayama (Toho), E. Komatsu (MPI), Onishi (Osaka P. U.),T. Oshima, M. Honma, D. Iono, N. Kuno (NAOJ), H. Matsuhara (ISAS/JAXA), M. Momose (Ibaraki), H. Nakanishi (Kagoshima) & Working Group (As of Dec. 3-8, 2012)
Nominal Specification
Dish diameter: 35 m (up to 50m)
Main observing frequency: 70−400 GHz
Highest obs. frequency: up to THz (with limited use of surface)
Beam size: 350GHz
Remote operation is available from Japan.
Timeline (Tentative)
2013− Survey design & conceptual design
2014−2017 R&D
2018− Start Construction
2023− Start Operations
Partners
CO Tomography; Blind CO Search
Survey Example of CO Tomography; D = 35 m, 1000 hours, 2 deg2 Survey with Imaging Spectrometer, Npix =100 & GHz (6 deg2 with Super-DESHIMA, Npix= 300)
LSS (Large Scale Structure) up to z ~ 5
CO luminosity Functions at various redshifts and CO SEDs for high-z galaxies can be obtained
Num Count dN/dz ~ 104 at z~2 for Npix = 300, RSD (Redshift Space Distortion) can be investigated to estimate growth rate of large-scale structure and dark energy
Merit of large single dishes
Confusion Noise ∝ D−1.4
Spatial Resolution ∝ D−1
Survey Speed ∝ D2
Speed of pointed Obs. ∝ D4
Proposed Instruments
Multi-chroic wide-field camera(s) covering 90 to 350 GHz (+ 650 GHz)
Multi-pix imaging spectrometers, e.g., at 70–400 GHz (e.g., “Super-DESHIMA”)
Heterodyne receivers, 70 GHz to 1 THz, + Ultra-wideband spectrometer
Heterodyne receiver array, e.g., at 100, 230, 350, 492 GHz
Other Proposed Surveys
ASTECAM (T. Oshima, NRO)
Multi-wavelength SMG survey for z = 1−5 & Establishing large sample of forming dusty galaxies (down to SMGs with SFR ~ 100 Msun/yr)
Blind [C II] survey to prove more distant universe, e.g., epoch of reionization (EoR) up to z ~ 7 or 8
High Spatial Resolution Mapping survey of distant SZ cluster to probe structure and mass of clusters, and blind SZ Cluster survey up to z ~ 2 to probe high-mass end of LSS
Spectral line survey to investigate chemical and physical evolution in core to protoplanetary disk
Galactic-plane survey & survey of nearby star-forming regions
Multi-color bolometer camera for ASTE based on the transition-edge sensor (TES) technology
270, 350, 670 GHz
Scientific interest: SMG search and photo-z
Cosmic history of star/galaxy formation
Evolution of the cosmic LSS at z ≧ 3
Phase I commissioning on ASTE was successful.
Phase I II
III
Test
Science operation
Date
2012/4-6
2013/3-4
TBD
Target frequency
270, 350 GHz
350, 650 GHz
No. of pixels
169, 271 pix
271, 881 pix
Field of View
7.5’ Φ
NEFD (mJy/√sec)
10, 35
35, 80
First light image of
the Moon at 270 GHz
Detector array
TESCAM dewar
Commissioning of ASTECAM
on ASTE 10-m (Apr, 2012)