マスタ タイトルの書式設定

Ryohei Kawabe (NAOJ)

Beyond ALMA

✦ ALMA:何がわかったか、何が足りないか ✦ LST: 何をやりたいか、どのような計画か、

ALMAへのボーナス効果 ✦ 最後に：small developmentsが未来を切り開く

I: Advent of ALMA

何がわかったか、 何が足りないか

ALMA opens new era

3

Hubble Deep Field and SCUBA map

- High Angular Resolution, ~ 0.01 arcsec; sharp radio images - High Sensitivity to reach the early universe (also thanks to

very unique characteristic of submillimeter emission in SMG)

✦  ALMA will contribute to elucidating galaxy formation and planet formation with exploiting extreme performance

Gaps in Protoplanetary Disks

Hughes et al. 1998

Cycle-0 unveiling exciting views of the universe, but still in starting point of climbing to the top.

Imagine how splendid the view is at the top!

4

ALMA Goal: 0.01” resolution ..

ALMA cycle-0 ACA

Bands 4 & 8 Polarization

Y+ Config (max. BL)

Band 10

Band-5, 1

ALMA Science Goals

5

Hubble Deep Field and SCUBA map

- High Angular Resolution, ~ 0.01 arcsec; sharp radio images - High Sensitivity to reach the early universe (also thanks to

very unique characteristic of submillimeter emission in SMG)

✦  ALMA will contribute to elucidating galaxy formation and planet formation with exploiting extreme performance

Gaps in Protoplanetary Disks

Dreams come true!

[OIII] detection at z=7.21! Inoue, Tamura+2016

Line-Emitter/redshift Search :ALMA is not so powerful?

✦  ASPECS: ALMA SPECtroscopiC Survey in HDF (PI:F. Walter) ✦  To unveil cosmic gas density evolution etc. ✦  preliminary results with ~ 20 hours - B-3: 10 emitter cand. - B-6: 11 candidates => one/ hour

Walter+2016

Dust gaps unveiled in disks :gas/pol imagings are still challenging?

✦ Dust Gaps in Class-II source TW-Hya (d=54 pc) ✦ Dust filtration due to a formed planet? - dust-β and pol. imaging constraints on grain size - gas gap image needed for planet mass estimate

B4+B6 Continuum Image Tsukagosi, Nomura, Muto +’16

Cyc-4 observations - 0.14” polarimetry ~ 6 hours - 0.1” (~5.4 au) & 0.2 km/s 13CO & C18O imaging (requested ~8 hours)

22 au gap

37 au gap

x 2-3 resolution needs x ~10 more in time

Central hole PI: Nomura Kanagawa+’15

PI: Muto Kataoka+’15, ’17

Needs More for ALMA?

✦ Sensitivity, especially in spectral line & Polarimetry ✦ Spatial Resolution, especially in continuum ✦ Spectral/Frequency Coverage for e.g., “spec-z” ✦ Field of View ✦ Time-domain Science ?

How can be improved in the future plans?

Synergy among ALMA, ngVLA, and SKA

✦ Cosmic Star Formation, Co-Evolution of Galaxies and SMBH, Large Scale Structure

✦ ALMA: Challenges to z~10 EoR with [CII], [OIII], dust etc.

✦ ngVLA: Challenges to z>5 with CO ladders ✦ SKA: Challenges to large scale structure at

z> 10 and star formation beyond z>5

✦ Special Note: multi-wavelength astronomy!

ngVLA is only array to detect CO at z=5?

ngVLA is only array to detect CO at z=5?

CO(8-7) CO(7-6) NGC6240/Mrk231

ALMA B4+B5 CI

ALMA still powerful!

Inevitable Barriers for Large Arrays

✦ Brightness Temperature Barrier ✦ Spatial Resolution Barrier ✦ Freq. coverage Barrier

✦ ALMA can go deeper and finer in the cool (thermal) universe

✦ Not easy for ALMA to overcome wide-field & wide freq coverage, time-domain problems

0.001

0.01

0.1

1

10

100

1000

10000

100000

1000000

10000000

0.1 1 10 100 1000

Freq. (GHz)

Brightness Temperature Sensitivity (R-J) : continuum case (0.01” beam/fixed hours assumed)

Beam Size : 1 K sensitivity assumed

10

100

1000

10000

ALMA

ngVLA

SKA

10 mas

100 mas

1”

b6 b7

100 10 1 0.1 1000

1 ALMA B6/7 is at the best

M82 (10 Msun/yr) x 5 at z= 10 (EoR)

1 µJy

10 cm

ALMA 20 hours 5σ ~ 34 uJy

λobs 1mm

Line　5σ

Continuum 5σ

ngVLA=5-10 x JVLA 20 hours

1 cm

Needs More for ALMA?

✦ Sensitivity, especially in spectral line & Polarimetry ✦ Spatial Resolution, especially in continuum ✦ Spectral/Frequency Coverage for e.g., “spec-z” ✦ Field of View ✦ Time-domain Science?

✦ Band-1 and -3 sensitivity can be improved by ngVLA

How can be improved in the future plans?

Needs More for ALMA?

✦ Sensitivity, especially in spectral line & Polarimetry ✦ Spatial Resolution, especially in continuum ✦ Spectral/Frequency Coverage for e.g., “spec-z” ✦ Field of View ✦ Time-domain Science?

✦  Band-1 and -3 sensitivity can be improved by ngVLA

✦ LST can develop new discovery space complementary to ALMA

How can be improved in the future plans?

II: LST

何をやりたいか, どのような計画か,

ALMAへのボーナス効果

New Challenges in 2030- ✦ Unveiling EoR & formation of first star,

Galaxies, SMBH through the cosmic time ✦ Time-domain Science - GRB, Magneters, Pulsars - FRB, GW-counter parts - Flares from stars, ✦ Extreme Physics in the Universe - Resolving BH shadow - CMB B-mode

New Challenges in 2030- ✦ Unveiling EoR & formation of first star,

Galaxies, SMBH through the cosmic time ✦ Time-domain Science - GRB, Magneters, Pulsars - FRB, GW-counter parts - Flares from stars, ✦ Planet Formation & Life in Space ✦ Extreme Physics in the Universe - Resolving BH shadow - CMB B-mode

LST

Basic Concept :Tentative Specifications

✦  Large Aperture: Diameter = ~ 50 m less confusion, confident counterpart ID, high sensitivity for line emitter search and point-like sources & transients such as GRB: ✦  Large FOV : F.O.V = 30 arcmin. diameter, Goal = 1.0 deg cosmological deep and wide-field survey & high cadence ✦  Main Frequency Range = 70 – 420 GHz well fit to Atm windows & “Major” Science Case covers up to ~ THz with the limited use of surface to maximize synergy with ALMA ✦  total surface rms ≤45 μm (El = 30-80 deg) with Active surface Control ✦  Possible site; ALMA site

Key Science of LST ✦ Exploration of Cosmic Star Formation History and

Large Scale Structures via two kinds of surveys - Multi-band Deep Continuum Survey over ~103 deg2 - Blind CO/CII line emitter search (Tomography) up to z~ 8, EoR, using imaging spectrograph (Blind vs multi-target spectroscopy still needs to be investigated, but blind can provide us with census of “non-biased” line emitters, in which strong-line but continuum-weak emitters will be included) ✦  Time-domain science via high cadence performance ✦ Covers wide range: SZ cosmology, VLBI, chemistry

RK+ in SPIE proceedings; White paper by Kohno, RK in prep

Yoichi Tamura / Large Aperture Sub/mm Single Dish Telescopes in the ALMA Era

CO/[CII] Tomography

RSD Redshift Space Distortion. / /

. , /

LSS Cosmic Large-Scale Structure/ ,

, . /,

CSFH Cosmic Star-formation History/ . .

/ . . , .,, .

Evolution of Galaxies. / ,

/ . ,

EoR Epoch of Reionization. ,, /

/ /

... and serendipitous discoveries,      

CO/CII vs HI Tomography 　10000 hrs SKA 1 surveys (SKA 1: 10% of full SKA)

1000 hrs LST+ super-DESHIMA (300 pix) survey Deep 2 deg2 70-400 4-15” ~ 100,000 ? (7~9) Y.Tamura+ in prep. GHz >1,000 (z>6)

Blue: Medium wide Green: Med. deep Red: Deep

SKA HI

LST CO/[CII]

EoR

Why LST/sDESHIMA so powerful?

s-DESHIMA 370 GHz

70 GHz

[CII]

Time-Domain Science Case

Inoue+2007

LST

z=20 GRB

GRB Orphan Afterglow (Totani+2002) GRB Reverse Shock at extremly high-z (Inoue+2007) - Absorption detection in GRB environments & intervening gas? LST can contribute to quick location determination & WB spectroscopy at same time

Simulation of GRB afterglow

Yoichi Tamura / Large Aperture Sub/mm Single Dish Telescopes in the ALMA Era

z = 30 GRB afterglow (1-12hr, 300GHz)5

arcm

inLST 50m

CCAT 25m

ALMA (mosaic)

Swift/BAT error circleASTE 10m

ALMA FoV (Band 7)

Flux density (mJy/B

)

1.0

–0.1

0.0

Movie is available on the LST web site

LST covers wide range of Science

● Wide-Field Spectroscopic Imaging

● Time-domain Science

Develop new discovery space complementary to ALMA

Planck 3.5 arcmin.

LST ~ 4 arcsec. ~ 60 µKRJ

LST Sky Coverage El > 25 deg

Planck 3.5 arcmin.

LST ~ 4 arcsec. ~ 60 µKRJ

LST Sky Coverage shared with SUBARU, TMT, JVLA/ngVLA

Wide Survey 1.1 mm with 1 deg FOV, 2 mJy/b 30 shallower than confusion limit 10^4 deg^2 870 hours

Deep 1.1 mm with 1 deg FOV, 0.7 mJy/b x10 shallower than confusion limit 10^3 deg^2 870 hours “Contamination” expected - 10^6 “bight” SMGs - > 1000 lensed SMGs

LST Galactic Plane Survey

Technical Feasibility Study

✦ Science Requirement & Technical Specification ✦ Operation condition & Operation Planning ✦ Optics Design ✦ Conceptual Design of Telescope Structure ✦ Surface Accuracy Budget Analysis ✦ (Very Preliminary) Cost Estimate ✦ AO application or Millimeter-wave AO (MAO)

under discussion

Optical Design for wide FOV

Richey-Chretien Optics for D= 50 m main reflector Lyot-Stop at Sub-refrector: Deffective ~ 46.7 m FOV ~ 0.7 deg. in diameter at 850 micron achievable But… - large mirrors Dsub-ref ~ 6.2 m #3 mirror ~ 7 m diameter - huge RX cabin needed (big impact on telescope mechanical structure?) - No aperture plane @main reflector

Takekoshi, Oshima + in prep.

very preliminary

Conceptual Design Double Sector Gears

Receiver Cabin

Elevator Collimator Tower

Tertiary & Forth Mirrors

The First Drawing of LST Conceptual Design; Major req. accommodated. Image Courtesy of

Mitsubishi Electric Company

Conceptual Design

Image Courtesy of Mitsubishi Electric Company

Top View

Back View

#3, & #4 mirrors limit the minimal size of receiver cabin..

Active Surface Control Required

45 µm rms needs careful mech/thermal design as well

2 m ~ 2m x 1m

Tentative Surface Error Budget for LST

RK+ in SPIE proceedings; White paper by RK, Kohno, in prep

& comparison with IRAM 30m Telescope

Error budgets for Gravity and Thermal Deformation can be smaller Wind-Load is current headache, some correction etc. needed

Key Instruments ✦ Ultra-Wideband Medium-Resolution Imaging Spectrometer

Array: Blind CO/[CII] Tomography Freq= 70 - 420 GHz & Npix of > 300 (~ 1000) ✦ Multi-Chroic Wide-Field Camera covering 2, 1.1, 0.85 mm, (+0.45, 0.35 mm) ✦ Multiple-band Heterodyne Array Receivers (~ 100 beams) + Ultra-wideband Spectrometers (for line survey)

Mm/submm multi-object spectrograph

MOSAIC => “Super DESHIMA” <= or “Super MOSAIC”…

Delft SRON High-Z Mapper

Combined Array: ALMA+LST

✦ 1 ~ 40% increase in correcting area ✦ 2 ~ keeping F.O.V. area with multiple beam or x2 increase only for 12m-LST correlat. ✦ 1+2 => > x2 increase in observing speed - F.O.V. 12m-LST ~ sqrt(P12m)*sqrt(PLST)

International Collaboration? ✦ Discussion via workshops - LSTWS2015: Large millimeter/submillimeter telescope in the ALMA era - Status of Other Telescopes updated e.g., Caltech ~ 30m survey telescope ✦ Recent Progress - European perspective: ~ 40m class similar to LST : A good-sign toward a future “40-50 m class” sub-mm single disk telescope in Chile as a single international project, although it will be hard to project and secure construction budget

III: 最後に

Small　is beautiful! Small developmentsの積み上げ

が将来を切り開く (+ALMAを使い倒す)

Examples of “Small” developments

✦  New Detector Technologies - TES Camera/Multiple- chroic TES - DESHIMA/DESHIMA 49 - Tsukuba-cam,… ✦  Super-resolution Imaging by Sparse Model. - Application to ALMA Data ✦  Millimeter-wave Adaptive Optics (MAO)

Super-resolution Imaging

✦ Conventional Imaging: CLEAN, λ/D limit ✦ Super-resolution by Sparse Modeling ✦ Applications to ALMA underway - continuum imaging - pol. Imaging - Spectral line imaging - selfcal, mfs etc

See Poster by M. Yamaguchi

Honma+2014

Akiyama+2017

Sparse Modeling: ALMA Original data: 0.51” x 0.43”

High-res. data: 0.18” x 013”

Image by Sparse Modeling

Consistent! Super-res w. small CB Comparison

HD142527

x 2-3 higher resolution

Millimeter-wave Adaptive Optics PI: Y. Tamura

まとめ

✦ ALMAは本当にpowerful ✦ ALMAは将来を映す鏡: ALMAで観測を進め

ると、将来何が必要かがだんだん見えて来る。 ✦ LSTは、ALMAを補佐しつつ新たな地平を目

指す(中型)計画。サイエンス、装置技術の検討を進めて行きたい

✦ Small projects (+アイデアを試すことも) are essential for our future.