31 October 2008
Report of the ANASAC to NRAO: Annual Face-to-Face Meeting
Attending: Baker (chair), Bally, Blain, Fall, Heckman, Johnson,
Johnstone, Prochaska, Shang, Stacey, Weinberger, Williams (by phone)
In addition to the formal charges to which responses follow below,
the ANASAC would like to offer unsolicited recommendations on several
other issues that were discussed at the face-to-face meeting.
(1) Future charges.
The ANASAC would like to consider future charges from NRAO regarding
(a) The drafting of a white paper on the scientific justification
for the development line item in the ALMA operations budget, as
an input to the upcoming U.S. decadal review. (This charge
would engage primarily the U.S.-based members of the committee,
and is viewed as sensible by the ASAC.)
(b) The provisions that will be made for allocation of ALMA
observing time, including how large proposals, director's
discretionary proposals, and joint proposals with other
observatories will be handled for the North American share
of ALMA time.
(c) The computational demands of offline data reduction by North
American ALMA users, including access to high performance
computers for analysis of complex datasets.
(2) Contacts with other groups.
The ANASAC would like to learn from NRAO how the recommendations
of the McCray
"Radio Futures" committee will couple with ALMA.
In anticipation of the time allocation charge suggested above,
the ANASAC may contact the JWST Science Working Group, the
Herschel Science Team, and equivalent groups to discuss the
prospects for joint ALMA/JWST proposals. We would encourage
parallel contacts between NRAO and STScI
at the directorial
level as well.
(3) ANASAC membership and meetings.
The diversity of background within the current ANASAC membership has
been valuable as the committee grapples with issues (e.g., user
grants) that are of interest to the entire North American community.
Since the committee is also being asked to consider many items of a
technical nature, the ANASAC encourages NRAO to make the next set
of new members people who already have expertise on (sub)millimeter
astronomy. In future years, the balance of expertise on the committee
can be tuned to match the ANASAC's evolving mission.
Regardless of background, the ANASAC recommends that in future years,
new members be designated before
the annual F2F
meeting, so that
they can have the option of attending the F2F
as non-voting visitors.
Arranging for such an overlap of outgoing and incoming members will
help the latter come up to speed on the committee's work.
The ANASAC recommends that planning for future F2Fs
allow for the
possibility of meetings that last more than one day, to give time
for more reflection on the agenda items and the committee's overall
mission. Future meetings should definitely
follow the precedent
begun this year, in which briefing material was provided to the
committee in advance of the F2F
(and was largely compiled from
presentations to other committees, in order to minimize reporting
burden on NRAO staff).
The ANASAC would like to thank NRAO staff for organizing and
preparing presentations for this year's F2F
RESPONSES TO CHARGES
The ANASAC has a standing charge to review the latest ASAC charges,
and provide input to the ASAC members. We ask that the ANASAC pay
particular to attention to the charge in which the JAO is asking
the ASAC to take a prominent role in defining the scientific
priorities for the ALMA development plan. Please discuss and
recommend how the ANASAC can facilitate a mechanism to solicit the
inputs and interests of the North American community and make sure
the ASAC deliberations encompass the needs of the NA community.
In the near term, discussion of ALMA development priorities is
being led by a 15-member group that includes six North Americans
(current ANASAC members J. Bally and A. Blain, former ANASAC
members M. Gurwell and C. Wilson, former MMA Advisory Committee
member J. Carlstrom, and current North American Project Scientist
A. Wootten). This group will make its initial response to the ALMA
Board in November 2008, with its efforts expected to expand and
develop through 2009. Informal contacts by members of this
group with colleagues at their home institutions and/or on the
ANASAC will yield immediate feedback from a subset of the
North American community. Input from broader cross-sections of
the community has been obtained at the second ("Transformational
Science with ALMA: Through Disks to Stars and Planets"; 2007
June 22-24) and third ("Transformational Science with ALMA: The
Birth and Feedback of Massive Stars, Within and Beyond the
Galaxy"; 2008 September 25-27) NAASC
science workshops. At the
latter event, one afternoon of the three days featured an
introduction to "The Future Evolution of ALMA" from North American
Project Manager A. Russell; breakout sessions to discuss key ALMA
Galactic and extragalactic science drivers; and a final unified
discussion (chaired by Blain) to synthesize a unified set of
On longer timescales, the ANASAC recommends that the exercise
at the third NAASC
workshop be used as a template for similar
"piggybacking" on future science meetings, whether they are
organized by NRAO or not, as recommended by the ALMA Board.
Such meetings might include future NAASC
(explicitly mentioned in the current NRAO Long Range Plan),
AAS and CASCA meetings, or smaller events with narrower but
ALMA-relevant themes. The miminum requirements for targeting
a meeting for a development discussion would be the attendance
of (a) a handful of technically proficient ANASAC members, NAASC
staff, and/or ALMA Project personnel who could help facilitate
brainstorming discussions, and (b) a strong North American
contingent. A series of such exercises would be relatively
low-cost; the desired goal would be a dynamically evolving white
paper on development priorities (analogous to the DRSPs) that
would correspond to the scientific
priorities of different
subsets of the North American community. A more informal
"piggybacking" could follow the example of the Spitzer Science
Center, which used its booth at pre-launch AAS meetings to
expose potential users to the capabilities of the observatory.
Encouraging visitors to the NRAO booth to simulate a sample set
of ALMA observations (in one of several scientific areas,
perhaps scheduled for particular times at a rate of ~4 per day)
and see what data could be delivered in how much integration
time would then prompt feedback about what ALMA can't (yet)
do, a source of input on development priorities.
Finally, the ANASAC would like to strike a note of realism: if
only individual compelling science cases can really change the
decision path for ALMA upgrades, NRAO will face the difficulties
that (a) community members have so many proposals to write already
that there will be little incentive to engage in "unicorn"
exercises for facilities that might or might not come to be, and
(b) no one wants to give away his/her best ideas to competitors.
Overcoming these activation barriers may be difficult unless
there is actually a formal solicitation for "ALMA 2020" proposals
that can be appropriately rewarded (e.g., with explicit
coauthorship on a development white paper). Logistical/technical
support from the NAASC
may also be appropriate.
Finalize the current ANASAC response to this charge: "The NRAO
asks the ANASAC to consider the issue of stimulating research in
preparation for the use of ALMA, e.g., wide-field surveys to
identify interesting targets, laboratory work on astro-chemistry,
or theoretical work on star and galaxy formation, and how such
preparatory research before ALMA is operational can be funded,
as well as recommending avenues by which the NRAO or other
organizations could promote such efforts."
The ANASAC discussed at length the full challenge of stimulating
research in preparation for ALMA before the advent of full
science operations, and came to the conclusion that the most
critical element of developing ALMA-related research programs
within the North American community is developing the human
capital required to execute them. That conclusion is the
motivation for the remainder of our response to this charge.
While it is being built by people with deep knowledge of mm and
submm interferometry, ALMA should advance the science interests
of almost all the broad observational astrophysics community in
North America. The capabilities of ALMA will enable the community
to build on its varied personal archives of data and professional
knowledge to advance our understanding of the Universe.
In this statement lie some important realities of bringing ALMA
online. The project and its builders must reach out to the wider
astronomical community, many of whom have not so far gained
experience of using mm/submm-wave interferometers. The project
i) retain support for healthy funding during construction, early
science and full operations, to ensure that a dynamic team of
graduate students and postdocs will be ready to capitalize
rapidly on Early Science data; and
ii) ensure that a healthy pool of potential ALMA employees are
Note that it is important to reach out beyond the existing
centers of excellence in submm astrophysics, to ensure that the
whole community is engaged. However, in terms of training,
continued operation of the existing facilities while ALMA is
opened up are crucial.
While we appreciate that the financial constraints imposed by the
advent of new capabilities usually requires sacrifice in existing
support, continuity in the community is very important. There is
some evidence that the breadth of the radio astronomy community
in the US may have been adversely affected by the commissioning
of the VLBA. While ALMA is a larger, and much-less-specialized
instrument than the VLBA, we feel strongly that the whole of the
North American scientific community will benefit from a vibrant
mm/submm community, which will help the wider community to benefit
from ALMA's arrival. We feel that the impact of ALMA will match
those of other flagship projects at complementary wavelengths,
like LSST, ELTs, and SKA; these facilities will be useful to
the broadest communities, although their development is in the
hands of specialists.
Furthermore, any additional expenditure will have to made either at
the expense of items within the ALMA construction or operations
budget, or else be supported by other avenues at NSF. The desire
to involve the widest community in preparations for ALMA is the
overriding goal, regardless of the source of funds.
(2) Training requirements
In general, the ANASAC supports the plans for community
involvement as laid out in the NAASC
budget. We offer here
our renewed justification for a number of key elements...
Graduate student support is one area where we think the wider
community could be introduced to ALMA. During early science, or
when carrying out archival, laboratory, or theoretical work
relevant to ALMA, graduate student support, allocated along the
lines of the NRAO scheme that applies to the GBT, could be used
to stimulate the interest of investigators and departments in
becoming involved with ALMA, directly supporting the youngest
investigators. This interest might be mercenary initially, but
having local experts learning about ALMA must be good for both
the project and the community.
Ongoing support from NSF for summer schools and support for REU
programs at institutes with existing mm/submm interests would be
an extremely important way to involve a larger fraction of the
community in ALMA-related efforts prior to full-scale operations.
We strongly support plans to implement such ALMA summer schools
as early science approaches and gets underway. In a similar vein,
we endorse the plan by NRAO staff members to develop an online
series of ALMA science lecture notes that can be used in standalone
form or as an adjunct to the excellent Condon & Ransom "Essential
Radio Astronomy" notes that are already available.
Opportunities for predoctoral students to work with NRAO staff
scientists on ALMA-related research projects are to be encouraged,
modulo the obvious first priority for NAASC
personnel of getting
the array up and running. To facilitate this goal, the ANASAC
recommends that the NRAO website feature a single, clearly
designated page that lists all staff scientists, along with
each individual's research interests and an indication of whether
he or she is currently open to taking on a student.
Experienced postdocs and faculty are likely to be of great help with
the commissioning of ALMA. In fact, given the difficulties with
recruiting project staff, they may in fact be essential, despite
sensibly being discouraged from making short visits in the ALMA
Operations Plan. For substantial sabbatical stays in excess of 3
months, as detailed in the Operations Plan, the Commissioning and
Science Verification (CSV) effort would surely welcome assistance,
subject to the approval of the project scientist. Full support
for visits by investigators to the NAASC
(also already in the
operations plan) should be provided.
The ALMA Operations Plan details three ALMA Fellows in Chile per
year, and 6+6 staff astronomers/scientists at the NA ARC in
Charlottesville means there is a heavy demand for trained
postdoctoral staff. In addition, 4 ALMA-related Jansky Fellows
are anticipated at any time. Note that the typical production
of students for CARMA and CSO since their inception has been about
6.4 per year. Including SMA, less than 10 observational/instrumental
students graduate in NA per year with experience of mm/submm-wave
We feel that student support is likely to involve more departments
with ALMA, starting at the grassroots level, while more senior
support is likely to ensure adequate North American staffing
during CSV and Early Science.
We would encourage the NSF to make utility to the ALMA project a
relevant positive criterion when assessing funding proposals.
The issue of user grants to support scientific exploitation of ALMA
is one where the competitiveness of US investigators could be
increased. It will be important to continue to consider the needs
of the community in the context of ground-based facilities at all
wavelengths. Note however, that the arrival of ALMA allows a natural
opportunity to investigate this issue in a timely manner.
(3) Outreach and international promotion
Support for members of the North American community to attend
astrophysics conferences and make presentations to emphasize the
importance of ALMA could be considered. This could include
observational, theoretical, and laboratory astrophysics. The
availability of more material for EPO for both the general public
and the wider astronomical community would also be welcome.
(4) Leverage from other facilities
In Europe, SCUBA-2, APEX, and near-IR/optical survey telescopes
appear to have important roles to play in revealing ALMA sources.
When it comes to identifying interesting targets for ALMA, it is
arguable that our international partners have more access to
suitable facilities, although note that the SPT/ACT, URO mm/submm
facilities, and the future space missions WISE, Herschel, and
Planck, along with the Spitzer archive, all have North American
access and involvement. Note further that Canada is a partner in the
JCMT, and thus there is direct access already by a fraction of
the North American community to SCUBA-2 surveys.
Future facilities with NA community access that would enable more
efficient identification of sources for ALMA to study include
LMT and CCAT. Existing facilities that might be willing to negotiate
greater North American involvement include APEX and JCMT, which
operate under agreements with specific time limits.
Commitment to involvement in new facilities must involve wide
community support and approval, but there are certainly opportunities
to obtain enhanced scientific output from ALMA by preselecting
targets more efficiently.
Archiving of other supporting data has been suggested as a possible
way to help the community exploit ALMA. At present, we feel that a
National Virtual Observatory and Google are in the best position to
coordinate and execute this kind of effort.
The ANASAC considers that maintaining a healthy US mm/submm-wave
community is essential to help the wider community to appreciate and
benefit from the investment in ALMA. We note that the ALMA operations
plan already addresses many of the anticipated needs of the community,
and we see additional student support as perhaps the most promising
route for early involvement of the general community with ALMA.
Our recommendations are that NRAO and NSF should
i) Support the development and maintenance of human capital and
expertise in ALMA, especially at the graduate student and postdoc
levels, as outlined in the current NAASC
ii) Consider the possibilities of enhancing the access of the
community to the products of mm/submm surveys, and to supporting
future surveys; and
iii) Take whatever steps possible to enhance public and community
outreach activity, and to ensure that documentation, tools, and
archives are readily accessible and publicized.
In the context of the recent NSF/AST suggestion of dealing with
ALMA-preparatory PI proposals, consider potential ways to inform
the community and to stimulate the submission of ALMA-preparatory
proposals in the upcoming round of NSF/AST call for PI Proposals
in November 2008. Also consider whether this suggested approach
would be a reasonable long-term method of instituting an ALMA User
The U.S.-based members of the ANASAC support the idea of broadly
based ALMA-preparatory PI proposals. Such a program has the
potential to spark early interest in ALMA and increase the future
U.S. user base. However, we remain somewhat confused by the
criteria NSF AST will use to identify "ALMA-related" proposals
at the current deadline during its preliminary information-gathering
exercise. Given this uncertainty, we feel it would be wisest for
the ANASAC and the NRAO not
to take any special steps to
encourage mention of ALMA by NSF proposers this year.
Looking ahead to future deadlines, the U.S.-based members of
the ANASAC recommend that (i) the NRAO Director work with NSF
AST leadership to come up with a clear statement of division
policy on pre-ALMA grant proposals that can be posted to the
NST AST and NRAO websites, and included in mailing to AAS
membership; and (ii) NSF AST leadership, with the greatest
urgency, convene a working group to examine possible mechanisms
for linking funding and observing time on U.S. ground-based
telescopes. Such a working group was identified a year ago
by NSF AST (with the endorsement of the ANASAC) as the
appropriate vehicle for considering the issue of ALMA user
grants in a panchromatic context. If convened soon (even in
a budget, telecon-only format), the results of such a working
group's deliberations will provide timely and valuable input
to the upcoming decadal review. To strengthen the impetus
for convening this working group in the face of NSF AST's
current inaction, the U.S.-based members of the ANASAC plan to
contact parallel advisory groups for other U.S. facilities; we
encourage similar coordination at the directorial level.
The NRAO asks the ANASAC for considerations and suggestions on
the potential use of the NA ALMA prototype antenna, once activities
at the ATF terminate in Q3 2008.
The ANASAC has considered several possibilities for the fate
of the NA protoype antenna. An initial
principally by Mel Wright, who expresses gratitude to the
participants at the ALMASIM meeting in Grenoble and other
community members who provided their input) is appended below
as background. Following our discussion at the F2F
ANASAC came to two main conclusions. First, the ANASAC
strongly endorses the view expressed at the F2F
that a formal
call for proposals to dispose of the prototype antenna would
be an unwanted distraction from ALMA commissioning at a critical
time for the project, and should be avoided. Second, we recommend
that the NA project manager investigate the following options,
order of priority:
(1) Contact university groups (including the SMA as well as
all U.S. groups supported by the URO program) to find out
the terms on which any of them would be interested (if
at all) in acquiring the protoype antenna. These contacts
should not be restricted to groups with interferometers,
since the prototype could still be useful in, e.g.,
testing instrumentation for CCAT.
(2) Explore the "South American options", namely (i) incorporation
into a millimeter VLBI network, and (ii) moving the prototype
to the APEX site and converting it into an APEX clone that
could share infrastructure and instrumentation with APEX
itself. The latter, "NAAPEX" scenario does not have a clear
path to operational funding, but would be worth at least
examining from a technical point of view, given the lack of
direct North American access to a southern survey telescope
at the present time.
(3) Consider options for leaving the prototype antenna in place
and allowing it to be used on an ad hoc basis for millimeter
VLBI experiments and/or instrmentation development by NRAO
and other groups. The ANASAC recognizes that the cost of
maintenance may make this a less attractive option for NRAO.
[Here follows the **INITIAL**
report from Mel Wright, provided
as grist for the mill rather than as an expression of the ANASAC's
i) VLBI experiment using one or both 12m antennas for 230 GHz VLBI.
The mm VLBI team are planning the next 1.3 mm VLBI experiment for
Spring 2009. An ATF antenna could be outfitted to participate while
the antennas are at ATF and are not starting to fall into disrepair.
This experiment is specifically aimed to measure the structure of SgrA
and would encourage ALMA/NRAO to actively participate in a global mm
VLBI experiment. When ALMA antennas at the ALMA site become available,
then these would be used for mm VLBI.
ii) Moving antenna(s) to CARMA, SMA, etc.
The ATF antennas could be moved to another, existing mm array site
and used as standalone single antennas, or incorporated into a
heterogeneous array. One possibility, which exploits the submm
capability, would be to replace one of the SMA antennas with one
of these antennas. A priority science topic for SMA was CII science.
A 12m antenna may be too small for this.
iii) Moving antennas elsewhere for future VLBI.
ii) and iii) are expensive options, and would require continued support
to operate. Noting that whilst neither CARMA nor the VLBI group
have money to support this, it would be a waste of these antennas
to destroy them, and a proposal could be written for specific goals.
The Vertex antenna arrived in relatively small pieces and could be
disassembled and reassembled. The ALCATEL antenna was shipped (via
special airplane) with the dish in one piece, so it's not clear what
its prospects are.
iv) Using as outrigger antennas to extend resolution at ALMA site.
The ATF antennas are non-standard and would require significant work to
make them work at the ALMA site. The Japanese prototype antenna was
moved and retrofitted/modified at substantial expense. The interface
to the transporters and various other things have changed completely
with the production antennas, so operationally it might be awkward to
integrate them (spares, lack of transportability, etc). Non-standard
antennas are harder to maintain, and add to operational costs. BIMA
moved only nine of the ten 6m BIMA antennas to the CARMA site for
v) Leaving them at the ATF.
This appears to be the best option. Moving them is likely too
expensive for any URO in the U.S. to pull off in the present funding
situation. The ATF antennas are superb mm/submm antennas on a well
supported and accessable site in the U.S. They could be used for
interesting science and for continued ALMA and mm-wave development.
Although local NRAO management may like the site cleared out, NRAO
could (1) continue to use them for development, or (2) make them
available to the community for science. Their use for development
has been extended several times, so that precedent exists; we note
that real time data processing may be hard to develop and debug in
Chile, as it requires tight coupling between on-line DSP and off-line
data processing. Optical offset pointing and primary beam pattern
correction of uv-data are other areas in which ATF-based development
could be useful. A VLBI experiment in situ could set a precedent
for (2). The availability of a superb mm/submillimeter antenna for
science and development would be a real asset to both NRAO and the
The big question is whether such a scenario puts a burden on the
ALMA project (supporting the antennas) and/or NRAO (through continued
use of the land). Once NA has a definite intention, we should contact
our international partners to make sure they too are on board, both
as a courtesy and perhaps also as a way to secure more resources
to make such a project feasible.
A mechanism for choosing between the options i through v should be
addressed. In this regard, NRAO might want to solicit short proposals
from the community for potential uses of the ATF antennas. Proposers
should address the proposed science to be done with the dish(es),
and discuss how they propose to fund relocation and operations.
- 19 Dec 2008