ASTE Status Report
Shin’ichiro Asayama and ASTE team1

Atacama Submillimeter Telescope Experiment (ASTE)• 10-m sub-mm telescope located at Pampla La Bola
within Chajnantor area
• Specifications of telescope:– Surface accuracy: 19um
– Pointing accuracy: 2” rms– Scientific Observing Time: 2,200h/year• Infrastructure:– Diesel generators x 2 (max 150kw – 220V)– Fuel tanks (15,000 L x 2, consumption 300L/d)– Satellite Network (1Mbps)– Weather Station, web cameras, etc• The prime objectives of ASTE operations:– to strength the proposals for the ALMA
– to provide advanced science capabilities for theEast Asian astronomers

ASTEALMA2Science Operation Policy• NAOJ Chile Observatory TAC: 90%– Detailed operation plan discussed at JSAC.
– 2 semesters of call for proposals provided East Asiancommunity (JP, TW, KR) from 2014.
– Guaranteed Time Observation (GTO)
The ASTE consortium contributes to developments of instrumentation on
ASTE, commissioning and science verification, and science operations. In
return for doing these contributions, members of the ASTE consortium canapply for GTO.

– Open Use Observations & GTO proposals are evaluated bysame referees.
– Observers remotely conduct their observations from Mitaka,
SPdA facility, and their institutes (for experts).

• Chilean Time (CT) evaluated by CNTAC: 10%

ASTE Instrumentation
Receivers
ReceiverType

DASH345
Band8Freq.
[GHz]

HPBW
[arcsec]

Npix Npol

Heterodyne 324-372

2212Heterodyne 385-500

1712Spectrometer
Spectrometer Type Quantization

BW
[MHz]

Nchan

Δf[MHz]

XF

512

1024

0.5

MAC
WHSF

FX

2-bit
3-bit

12840962048

0.1254096*

1.00.5ASTE Science Operation –Status

ASTE Science Operation - Status
Trends in the number of publications.
• Publication of CATS345 is the highest. Publication of AzTEC sporadic.
• The number of Band 8QM data is still not enough.
- Need further promotion (Demo science data released in Nov 2017.)

ASTE Science Operation - Status
Accepted (ABC-rank) ALMA proposals in EA that used ASTE

250.35N. of Proposals

0.25
150.200.15

100.1050.05
00.00
Cycle 1

Cycle 2

Cycle 3
NumberCycle 4
Ratio

Cycle 5

The ratio to the total EA proposals

0.3020ASTE Science Operation - Status
Trend of the Total open use time and the Number of Proposals.

FY 2017OpenUseChileApplied

Accepted

25205 (by Chile TAC)ASTE Science Operation - Status2017 Open Use ：2017 Jun – Sep (available time ~ 800 hours)• Receivers: 345 GHz and 492 GHz heterodyne receivers.
• Spectrometers : MAC (BW[MHz]: 512/128 )/WHSF (BW[MHz]: 4096/2048)

East Asian TimeTotal

345GHz492GHz

BothChileanTime(345GHz/492GHz)# submitted

251195Requested time [h]

905

329

413

163

# accepted

209745

Accepted time [h]693278279136122

Oversubscription (in #)

1.3

1.2

1.3

1.3

ASTE Science Operation - Status
44% Execution (=359 hours of 815 hours) due to several issues.
• Snowstorm: Lost~1.5 month of our 4 month schedule.
 Not enough commissioning time for the new 3 cartridge cryostats No Chilean time observation• Power Generator problem
 Due to low temperature, ASTE power generator stopped because of fuelpipe plugging with paraffin deposition on August 18th.
• MAC Spectrometer trouble
 The digitizer of the MAC Spectrometer system was ran down in July
2017. Most of high resolution observations were not able to beexecuted.
Toward 2018
• 456 hours observation will be carried over to 2018.
• We gave up the recovery for the MAC spectrometer system because it is too
old (~20 years old).WHFS high resolution mode will be offered in 2018.

DESHIMA
Commissioning ReportDESHIMA Commissioning on ASTE
• DESHIMA (DeepSpectroscopic High-redshift
Mapper– An on-chip filterbank
spectrometer withkinetic inductancedetectors (KIDs).
• DESHIMA on the 10 m ASTE
telescope.
– Phase-1: 330-370 GHz
band with 49 spectral
channels (prototype).
– Phase-2: target band
240-720 GHz and 2spatial pixels).
Filter-bank chip (design: 49ch, F/dF = 350, 326-368 GHz)

Aim of the 2017 Campaign❖ Baseline goal•

Test end-to-end operation of the DESHIMA system on ASTE, and confirm
that we understand everything consistently between the lab and on ASTE.
•

Interface checks•

Characterization of KIDs on ASTE•

Identify problems that can be found only by an actual installation, and not in the lab.

•In practical terms:•

Full success: we are able to see continuum emission from a planet, we understand theresponse, and the cryostat can stay in Chile•

Success: we are able to learn new lessons by operating KIDs in the ASTE cabin, eitherwith or without signal from the sky.

•Failure: we learn only problems that we could have addressed and solved in the lab.

❖ Bonus goal•

Detection of an astronomical line signal using an on-chip filterbank.

– If successful, this will be the first-light for a filterbank technology by any group.

13

First light of DESHIMA on ASTE:
on-chip filterbank spectrometer
Installed on ASTE since Oct 2017,DESHIMA has detected multiple
astronomical sources in bothcontinuum and line emission.
This is the first actual operationof an on-chip filterbank
spectrometer on a telescope.
Details to be presented by next presentation

ASTE Current Issues

ASTE Current Issues• MAC Spectrometer trouble
⁻ The digitizer of the MAC Spectrometer system was ran down in July
2017. We gave up the recovery for the MAC spectrometer systembecause it is too old (~20 years old).WHFS high resolution mode will beoffered in 2018.
• AZ Problem
⁻ During DESHIMA commissioning session, ASTE has gotten stuck/lockedon Nov 26th.
⁻ There is an issue on AZ mechanism. The root cause of this issue is underinvestigation by MELCOMid-term
Operation Plan

Medium-term Operation Plan
• Steady-state science operations with ASTE future
instruments• To maximize observing time for EA and Chileancommunity.
• To enhance synergy with ALMA and othertelescopes including NRO 45m.
• ASTE Development Project to be extendable toALMA.

Spectroscopic Observations•••

New 3-cartridge cryostat– Operate 3 cartridge-type receivers simultaneously.
Cartridge-type receivers– New 345GHz-band/ASTE BAND8– 0.9/1.3THz-RX (The University of Tokyo)– 230GHz-RX (The University of Electro-Communications)– 1-beam/4-beam BAND7+8 developed by KASIGPU Spectrometer developed by KASILast year (2016/6/23)

Blanking
platesB8 Receivers were inserted
to fill with 3 receiver ports

Updated mixer (2017/2/8)

Thermal load test cartridgewith sensors and heaters

ASTE Summary• The NAOJ Chile Observatory has established steadystate science operations of ASTE at 345 GHz and 450
GHz• The mid-term operation plan of ASTE future
instruments has been developed, with a long term
vision that is connected to ALMA development andupgrades.