LOFAR1 production observing

LOFAR will perform regular production observations till the end of Cycle 20 (31 May 2024). From June 1^st, efforts will focus on bringing LOFAR2.0 on-sky. Therefore, regular observations are stopped after this date because they conflict with these activities. Since LOFAR1 functionality will still be available till September 1^st, some already defined observing campaigns (including remainders from Cycle 20 projects and commissioning observations) will continue in the period June-July-August, but on a best effort basis and on a shared risk.

LOFAR Family Meeting 2024

The LOFAR family meeting 2024 will be held from 3-7 June in Leiden, the Netherlands. Registration is open and will close on May 24. Details about the meeting is available here. We hope to see you in Leiden. If you have any questions, please contact us via lofarconf@strw.leidenuniv.nl.

LOFAR Data School 2024

The 7th LOFAR Data School happened at ASTRON in Dwingeloo from April 15-19, 2024. There were 44 registered participants in total, coming from all around the world. The participants got to attend several lectures and tutorials hosted by experts, and a trip to the LOFAR core. For more details and access to the school materials please visit the official website.

Data staging and downloading from the LTA sites

Data staging and downloads from the LTA sites were stable in the past few weeks, except for the few planned maintenance days that the services were unavailable. Planned maintenance days are always mentioned on the LTA portal. Contact SDC-Helpdesk if experiencing any issues with staging and downloads.

• 38 stations are operational in the Netherlands: 24 core and 14 remote stations. 14 international stations are in operations: DE601, DE602, DE603, DE604, DE605, FR606, SE607, UK608, DE609, PL610, PL611, PL612, IE613, LV614.
• New international stations will be built in Italy and Bulgaria in the coming years. Both stations will be equipped with LOFAR2.0 hardware, whose installation/rollout is expected in 2025.
• Antenna elements of all stations are performing nominally, except, CS005, CS030, CS103 and RS503 HBAs, and RS210 LBA that have between 16 and 23% of non-operational elements. Those elements are either broken to be fixed or broken beyond repairs. The overview of non-operational antenna elements of both LBAs and HBAs is available here. At a station level, all stations were online for most part of the period under consideration, except, RS407 and DE601. The fiber connection to RS407 has been severally cut; it may take longer to get the network connection restored due to the extent of the problem. The issue with DE601 was due to the flooding of the station that happened on July 14/15, 2021. ASTRON maintenance engineers visited the station a couple of times, with the last one during 5-7 February 2024 to replace the broken RSP boards, power supply units, and as well resolved all LBA ground cables with problems. Unfortunately, the power outages are still re-occurring, so the Engineers are planning another visit in the coming weeks to try resolve the problem of the station.
• Moreover, no failures occurred on CEP hardware/software over the past couple of months. A major upgrade of the processing cluster is planned to happen later this year or early next year as part of the LOFAR2.0 project.

• Cycle 20 observing campaign started on 1 June 2023 and will run till 31 May 2024. LOFAR operations are subject to a possible extension as mentioned earlier. PIs can see their projects directly in TMSS. The public version of the observing schedule in TMSS may be found here. The user manual of TMSS is also found here.
• At the end of the first ten months of observations (till March 28, 2024), we have done about 7248 hours of successful production observations. This translates into an observing efficiency of 65% and a completion level of 87%.

LOFAR Development program (W. van Cappellen)

• First fringes have been observed with the LOFAR2.0 Test Station. On February 1^st, the signals from the first LOFAR2.0 station (CS001) were correlated with those from a LOFAR remote station (RS503) resulting in these fringes. These fringes represent a major milestone in the verification of the LOFAR2.0 hardware, firmware, and software.

• The rollout of the White Rabbit clock distribution system to the Remote Stations continued. The map shows the position of all remote stations, the color code indicates upgraded stations (green), a station where the WR is installed but not yet connected (orange), stations to be upgraded (gray and blue).

• The electric components for upgrading all existing stations and to build two new LOFAR2.0 stations are secured and available.
• This month, the modules for the two LOFAR2.0 Production Test Stations will be delivered and be ready for integration in the Subracks and verification in the Integration Test Facility (ITF) in Dwingeloo and Westerbork.

SDC program (J. Swinbank)

• Gearing up for LOFAR2.0 Commissioning

FAs I write this, we’re getting ready for the LOFAR2.0 Commissioning Event, which will take place on 10 April. This is a really exciting time for the LOFAR community as a whole, and we certainly share in that excitement in the ASTRON SDC. We’re really looking forward to engaging with an ever-wider community, to share the work that we’ve been doing over the last several years, and to solicit your help, feedback, and suggestions on the pipelines and services we are preparing for LOFAR2.0. The next couple of years are going to be hard work, but definitely worth it.

• Introducing LUDWIG, LOFAR’s new proposal tool

ASTRON’s “Rainbow” development is now hard at work on LUDWIG, the new proposal tool for LOFAR2.0 – a replacement for Northstar. Building on our past experiences with Northstar and learning from best practice developed at other observatories (like Hedwig from EAO), we are putting together a new tool that is designed to be fast, flexible, streamlined, usable – and customized to provide exactly the functionality needed to support LOFAR2.0 operations. LUDWIG is a major area of focus for the SDC Development Programme over the next few months; we’re looking forward to delivering a version ready for wider testing and commissioning by the summer of this year. See the screenshot attached for a preview of the work that’s currently in progress.

• Upcoming release of the LINC LBA pipeline

The LINC LBA pipeline, which provides direction-independent calibration of LOFAR data, is nearly ready for its first release. This is a really crucial step, as it brings capabilities for working with LBA data to the well-tested pipeline execution system that we’ll be using to support LOFAR2.0 operations. The development of LINC LBA has been a major effort by the Rapthor development team and has drawn extensively on expertise from across the LOFAR community – with a particular shout out to the LiLF system developed by Francesco de Gasperin. Watch out for LINC 1.0 hitting code repositories soon and join in with the LOFAR2.0 commissioning effort to give us feedback and help get the pipeline ready for operations.

Commissioning towards LOFAR2.0 on-sky (M. Brentjens, R. Pizzo, Carla Baldovin, Cees Bassa, Marco Drost, Boudewijn Hut, Marco Iacobelli, Emanuela Orru, and Tim Shimwell)

• With the LOFAR2.0 system upgrade well underway and development activities taking place at various levels to deliver functionalities ready for the next-generation LOFAR operations, commissioning to bring the LOFAR2.0 system on-sky has started. This crucial activity will make sure that the set of functionalities and tools delivered by the development programs are properly integrated in the operational environment, scaled according to the expected throughput, and deliver the data quality that enables the science that inspired and guided the 0 developments in the first place.
• We identified three commissioning areas in which work will be needed: telescope, pipelines, and operations. The work will require various levels of expertise as it will encompass the entire observing and processing systems. Engagement of various groups and users within and outside ASTRON is therefore crucial. We have realized this through a series of ASTRON-internal and external events that delivered an up-to-date view of the current status of the developments and plans for commissioning. Slides, recording, and minutes of the event held with the LOFAR community on 10 April can be found here. A follow-up Q&A session will take place within the next couple of weeks (announcement to go out soon).
• The 3 commissioning working groups will give momentum to the commissioning activities. We already anticipate that commissioning days will take place frequently. These will be crucial to discuss the status of the work, present and solve issues quickly, and plan the further work toward a successful LOFAR2.0 system on-sky.
• It is still possible to sign up for the commissioning groups in this Miro board. The coordinators of the working groups will be in regular contact with the participants.
• We anticipate that the Monday afternoon of the forthcoming LOFAR Family Meeting will be largely dedicated to commissioning topics and therefore solicit the community to participate.

The dates of LOFAR Status Meetings, roll-outs and stop days are listed in an online calendar that is available here.