The ALMA Cycle 8 2021 Proposal Process
On August 6, 2021, the Joint ALMA Observatory (JAO) notified Principal Investigators (PIs) theresults of the Cycle 8 2021 Call for Proposals, completing a process that began with the Cycle
8 pre-announcement last December. The proposal review process selected 253 high-priority
programs (Grade A + B) that will be added to the observing queue when Cycle 8 observations
start on October 1.
The ALMA Cycle 8 proposal call and review process was extraordinary in several aspects.
● Despite the challenging work conditions imposed by the pandemic, the community
submitted 1735 proposals that requested over 26,000 hours on the 12-m Array, far
exceeding the time requested in previous cycles. With 4300 hours available on the 12m Array, Cycle 8 was one of the most competitive cycles for ALMA time to date.
● The proposal review process had unprecedented participation by the community.
Between the introduction of distributed peer review and the continuation of panel
reviews for the larger proposals, over 1000 people participated in the review process
to help determine the observing program for Cycle 8.
● For the first time, ALMA required proposals be written in a dual-anonymous fashion,
where the identity of the proposal team remains hidden to the reviewers.
● Because of the ongoing travel restrictions imposed by the pandemic, the panel
reviews were held virtually.
Any proposal review process relies on the support and commitment of the community. Thiswas especially true in Cycle 8 with distributed peer review and the need for virtual panel
meetings. ALMA is indebted to the community for their enthusiasm and support for this newprocess.
Given the significant changes in the proposal review process implemented for Cycle 8, theJAO is conducting a detailed analysis of the results to identify any potential biases and is
carefully considering the feedback from reviewers and PIs. In the coming months, a detailed
analysis of the distributed peer review process will be made available. The summary below
presents an overview of the review process and its outcomes.
Dual-anonymous proposal review
ALMA monitors the results of each proposal cycle to identify systematics in the proposal
rankings. Dual-anonymous proposal review was instituted in Cycle 8 to further reduce biases
and make the review process as fair as possible for all users. The vast majority of thecommunity adapted readily to the guidelines and anonymized their proposals successfully.
Only nine proposals were deemed to have significantly deviated from the guidelines and wererejected by the JAO. The feedback from reviewers has been overwhelmingly positive, wherereviewers thought dual-anonymous made the process fairer and allowed them to focus thereview on the science and not the proposal team.

1Distributed peer review
Distributed peer review was used in the Cycle 8 main call for proposals requesting less than
25 hours on the 12-m Array or less than 150 hours on the Morita Array (aka. Atacama
Compact Array, or ACA) in standalone mode. One thousand sixteen astronomers reviewed atotal of 1497 proposals. Most reviewers read either ten proposals (67% of the reviewers) or
twenty (23%). The process ran smoothly, and reviewers praised the ease of use of thesoftware tools. Reviewers also provided many valuable suggestions on how to improve theprocess that will be considered for Cycle 9.
Stage 1 in the distributed peer review process is mandatory, and all but one of the reviewers
successfully submitted their Stage 1 ranks and reviews. In the optional Stage 2, reviewers had
the opportunity to read the comments from other reviewers and, if needed, revise their ranksand reviews. Five hundred ninety reviewers participated in the Stage 2 process, and 355
reviewers modified their ranks or reviews.
Panel reviews
The ALMA Review Panels (ARPs) met June 21-25 and the ALMA Proposal Review Committee(APRC) met June 29-July 1. The main outcomes of the ARP discussions are a ranked list of theproposals requesting between 25 and 50 hours on the 12-m Array and a down selection of
the Large Programs. These Large Programs are then further discussed by the APRC, which
consists of the panel chairs and at-large members.
The virtual meetings were held from 11 to 14 UTC each day. The different time zones of thereviewers, from UTC-7h to UTC+9h, meant that some participants started their panel
discussions as early as 4 am local time while others ended the discussions as late as 11 pm
local time. The reviewers exhibited extraordinary dedication and patience through the daily
zoom meetings!

Figure 1: Requested time per array (left panel) and the oversubscription rate by region (right panel) per cycle. The requested
time on all arrays increased significantly in Cycle 8, resulting in the highest oversubscription rates since Cycle 0.

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Proposal statistics and results
Users submitted 1735 proposals for 26,325 hours of 12-m Array time in Cycle 8. While thenumber of Cycle 8 proposals is comparable to that in Cycle 7 (1773), the requested time is
37% higher (Figure 1, left panel). As a result, the oversubscription rate in Cycle 8 is the highestfor ALMA since Cycle 0 (Figure 1, right panel). Unfortunately, many excellent proposals could
not be scheduled because of the high oversubscription. Table 1 and Table 2 present theselection statistics grouped by regional affiliation and scientific category, respectively. Figures
2-4 show the time assigned to the Grade A and B proposals by region, science category, andreceiver band. Overall, 15% of the proposals were accepted with priority Grade A or B.
Following advice from several committees, ALMA continues to encourage larger, more
ambitious programs. In Cycle 8, the cap in the amount of time allocated to Large Programs(15%) was replaced with a floor (10%) that represents the minimum amount of timeprioritized in the queue-building process for proposals requesting more than 25 hours on the12-m Array. As shown in Figure 5, the community responded enthusiastically to thesechanges. The number of Large Programs submitted increased to 40 in Cycle 8 from 14 in Cycle
7, and the number of proposals submitted that request between 25 and 50 hours increased
to 198 from 97.
Figure 6 shows the percentage of proposals assigned priority grades A or B as a function ofthe estimated execution time on the 12-m Array. The success rate, including Large Programs,
is largely independent of execution time, although the shortest programs (0-5 h) had a lower
success rate than 10-40 hours proposals. The following 6 Large Programs are scheduled forCycle 8 based on the recommendation from the APRC, which represents the largest allocation
to Large Programs in a given cycle by both the number of proposals and 12-m Array time.
1. AGE-PRO: the ALMA survey of Gas Evolution in PROtoplanetary disks(2021.1.00128.L)
PI: Ke Zhang (NA); coPIs: Ilaria Pascucci (NA), Paola Pinilla (EU), and Laura Pérez (CL)
2. ACES: The ALMA CMZ Exploration Survey (2021.1.00172.L)
PI: Steven Longmore (EU); co-PIs: Diederik Kruijssen (EU), Jonathan Henshaw (EU),Elisabeth Mills (NA), Paul Ho (EA), Cara Battersby (NA), Izaskun Jimenez-Serra (EU),
Adam Ginsburg (NA), and John Bally (NA)
3. CRISTAL: a survey of gas, dust and stars on kiloparsec scales in star-forming galaxies
at z ~ 4-5 (2021.1.00280.L)
PI: Rodrigo Herrera-Camus (CL); co-PIs: Manuel Aravena (CL), Natascha Forster
Schreiber (EU), Ilse De Looze (EU), Justin Spilker (NA), Ken-ichi Tadaki (EA), and Jorge
González-López (NA)
4. Bulge symmetry or not? The hidden dynamics of the Far Side (2021.1.00869.L)
PI: Lorant Sjouwerman (NA)
5. exoALMA (2021.1.01123.L)
PI: Richard Teague (NA); coPIs: Myriam Benisty (EU), Stefano Facchini (EU), Misato
Fukagawa (EA), and Christophe Pinte (EU)3

6. ALMA JELLY - Survey of Nearby Jellyfish and Ram Pressure Stripped Galaxies(2021.1.01616.L)
PI: Pavel Jachym (EU); co-PIs: Ming Sun (NA) and Masafumi Yagi (EA)
Table 1: Summary of submitted and accepted proposals

Chile

East Asia

Europe(CL)

(EA)

(EU)

North
America(NA)Open Skies

Total

Submitted Proposals
Number of proposals
76389
721
484
65
1735
12-m Array time (hours)
1308
5445
11066
7668
838
26325
7-m Array time (hours)
862
4542
4447
4602
394
14846Total Power Array time (hours)
4204537
3918
4822
10613802
Subscription rate
12-m Array (4300 h offered)
3.0
5.6
7.6
5.3
N/A
6.1
7-m Array time (3000 h offered)
2.9
6.7
4.4
4.5
N/A
4.9
Total Power Array (3000 h offered)
1.4
6.7
3.9
4.8
N/A
4.6
Grade A & B projects
Number of proposals
296771
833253
12-m Array time (hours)
383
870
1310
1321
30
3914
7-m Array time (hours)
385
677
518
100202581
Total Power Array time (hours)
12648646285201927
Grade C projects
Number of proposals
135294677233
12-m Array time (hours)
231
658
1047
982
126
3044
7-m Array time (hours)
49238
494
156
0936
Total Power Array time (hours)
0286
0370323
Regional distribution of all submitted proposals and the proposals recommended for scheduling with grades A and B, andGrade C. Note: subscription rates do not apply for Open Skies since all regions contribute observing time for proposals fromPIs who are not affiliated with any of the ALMA regions.
Table 2: Proposals by science category
Category 1 Category 2 Category 3 Category 4 Category 5
Total
Submitted Proposals
Number of proposals
434
386
465
320
130
1735
12-m Array time (hours)
8570
5940
5189
5292
1334
26325
7-m Array time (hours)
1272
5931
6037
971
635
14846
Total Power Array time (hours)
304
5058
8155
31253
13802
Grade A & B projects
Number of proposals
7457
66
40
16
253
12-m Array time (hours)
1308
836
829
787
154
3914
7-m Array time (hours)
149
1126
1002
141
162
2581
Total Power Array time (hours)
0335
1538
054
1927
Grade C projects
Number of proposals
6955
603910233
12-m Array time (hours)
1060
788
633
461
1013044
7-m Array time (hours)
260
350
312015936
Total Power Array time (hours)
0149
174
00323
Category 1: Cosmology and the high redshift universe; Category 2: Galaxies and galactic nuclei; Category 3: Interstellar
medium, star formation, and astrochemistry; Category 4: Circumstellar disks, exoplanets, and the solar system; Category 5:
Stellar evolution and the Sun.

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Figure 2: Distribution of execution time for Grade A and B projects by region for the 12-m (left), 7-m (center), and Total Power(right) arrays.

Figure 3: Distribution of execution time for Grade A and B projects by scientific category for the 12-m (left), 7-m (center), andTotal Power (right) arrays.

Figure 4: Distribution of execution time for Grade A and B projects by receiver band for the 12-m (left), 7-m (center), andTotal Power (right) arrays.

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Figure 5: Number of submitted 25-50 hours proposals (left) and Large Programs (right) by cycle.

Figure 6: Fraction of submitted proposals assigned Grade A and B as a function of the estimated execution time on the 12-m
Array. The error bars are 1 sigma from Poisson statistics.

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As ALMA has encouraged and accepted larger programs, the overall number of accepted
proposals will decrease naturally given the limited observing time. Figure 7 (left panel) shows
the mean and median time requested on the 12-m Array for Grade A+B proposals in eachcycle. The typical accepted proposal now needs about 12 hours on the 12-m Array, which is a
49% increase over Cycle 7. As a result of this increase, 234 Grade A+B proposals wereaccepted in Cycle 8 that require the 12-m Array, compared to 470 such proposals in Cycle 4(see Figure 7, right panel). Relative to Cycle 7, the number of accepted high priority 12-m
Array proposals declined by 35%.

Figure 7: (Left) The requested 12-m Array time per proposal that has been assigned priority Grade A or B. (Right) The numberof proposals assigned Grade A + B that request the 12-m Array versus proposal cycle.

Acknowledgements
We thank the 40 members of the review panels for their participation in the review process.
The proposal review committee was chaired by Professor Raffaella Morganti, and included
the following panelists:
Loreto Barcos-Muñoz
Akio Inoue
Miriam Rengel
Maruša Bradač
Nissim Kanekar
Anne Sansom
Hannah Calcutt
Adam Kobelski
Satoko Sawada-Satoh
Carlos De Breuck
Jin Koda
Yoshito Shimajiri
Eiichi Egami
Melanie Krips
John Silverman
Edith Falgarone
Brenda Matthews
Kazuo Sorai
Laura Fissel
David MeierJohn Tobin
Viviana Guzman
Yusuke Miyamoto
Matías Vidal
Christian Henkel
Kristina Nyland
Jeff Wagg
Rodrigo Herrera-Camus
Joana Oliveira
Liliya Williams
Saeko Hayashi
Alain OmontMark Wyatt
Hiroshi ImaiGergö Popping
Hsi-Wei Yen
Hanae Inami
Thomas Puzia
Ke Zhang
We would also like to thank the over 1000 reviewers who took part in the distributed peer
review process, whose participation was essential to the success of the Cycle 8 proposal call.
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