BARREL 1U Tri-axial Fluxgate Magnetometer (MAGN) Magnetic Field Data, no Gain Correction, not Despun, Level 2, 0.25 s Data

Three axis DC magnetometer data with nominal conversions applied. Data are neither gain corrected nor despun.

The BARREL Mission was a multiple-balloon investigation designed to study electron losses from Earth's Radiation Belts. Selected as a NASA Living with a Star Mission of Opportunity, BARREL was designed to augment the Radiation Belt Storm Probes, RBSP, mission by providing measurements of the spatial and temporal variations of electron precipitation from the radiation belts. The RBSP mission has since been renamed the Van Allen Probes mission. Each BARREL balloon carried an X-ray spectrometer to measure the bremsstrahlung X-rays produced by precipitating relativistic electrons as they collide with neutrals in the atmosphere, and a DC magnetometer to measure ULF-timescale variations of the magnetic field. BARREL observations collected near latitudes close to either the antarctic and arctic circles at stratospheric altitudes at about 30 km. The BARREL instrumentation provided the first balloon measurements of relativistic electron precipitation while comprehensive in situ measurements of both plasma waves and energetic particles were available. Also, the BARREL data has been used to characterize the spatial scale of precipitation at relativistic energies.

The initial pair of balloon campaigns that were conducted initially during the Austral summer months of January and February of 2013 and 2014 with launches from two stations located in Antarctica: the British base located at Halley Bay on the Brunt Ice Shelf and the South African SANAE IV base (SANAE stand for South African National Antarctic Expedition) located in Vesleskarvet, Queen Maud Land. For the 2013 and 2014 the balloon campaigns, the launch plan was designed to maintain an array with about five payloads spread across about six hours of magnetic local time, MLT, in the region that magnetically maps to the radiation belts. Thus, the BARREL balloon constellation constituted an evolving and slowly moving array able to study relativistic electron precipitation from the radiation belts.

Later campaigns were undertaken in 2015 and 2016 from the Esrange Space Center located in Kiruna, Sweden. The 2015 and 2016 campaigns were undertaken in coordination with the Van Allen Probes mission, the European Incoherent Scatter Scientific Association, EISCAT, incoherent scatter radar system, and other ground and space based instruments. Seven balloon launches occurred during the August 2015 BARREL campaign. A total of eight flights occurred during August 2016.

Summing over the four BARREL campaigns, over 50 small, approximately 20 kg, stratospheric balloons were successively launched. The website creeated and hosted by A.J. Halford (see Information URL below) reports that: "By the end of the campaigns, there were over 90 researchers coordinating on a daily basis with the BARREL team working on 7 different satellite missions, 1 other balloon mission, and way too many ground based instruments to count." Although the BARREL mission launched only balloons during the years from 2013 to 2016, research using data collected on these flights is ongoing, so stay tuned for updates! All data and analysis software are freely available to the scientific community.

The information listed above in this resource description was compiled by referencing several BARREL related resources including primarily the Millan et al. (2013) Space Science Reviews publication, the BARREL at Dartmouth mission web site, and the website maintained by A.J. Halford.

The current release of all BARREL CDF data products are Version 10 files.

BARREL will make all its scientific data products quickly and publicly available but all users are expected to read and follow the BARREL Data Usage Policy listed below.

BARREL Data Usage Policy

BARREL data products are made freely available to the public and every effort is made to ensure that these products are of the highest quality. However, there may occasionally be issues with either the instruments or data processing that affect the accuracy of data. When possible, a quality flag is included in higher level data products, and known issues are posted in the BARREL data repository. You are also strongly encouraged to follow the guidelines below if you are planning a publication or presentation in which BARREL data are used. This will help you ensure that your science results are valid.

* Users should always use the highest version numbers of data and analysis tools. Browse/quick-look plots are not intended for science analysis or publication and should not be used for those purposes without consent of the principal investigator, PI.
* Users should notify the BARREL PI of the data use and investigation objectives. This will ensure that you are using the data appropriately and have the most recent version of the data or analysis routines. Additionally, if a BARREL team member is already working on a similar or related topic, they may be able to contribute intellectually.
* If BARREL team members are not part of the author list, then users should Credit/Acknowledge the BARREL team as follows: We acknowledge the BARREL team (PI: Robyn Millan) for use of BARREL data.
* Users are also requested to provide the PI with a copy of each manuscript that uses BARREL data upon submission of that manuscript for consideration of publication. On publication, the citation should be transmitted to the PI.

The BARREL PI can be contacted at: [e-mail].

An online copy of the BARREL Data Usage Policy document can be found at: https://barrel.rmillan.host.dartmouth.edu/documents/data.use.policy.pdf.

已应用标称转换的三轴直流磁强计数据，该数据未进行增益校正，也未进行消旋处理。

BARREL任务是一项多气球科考计划，旨在研究地球辐射带的电子损失现象。该任务被选为NASA《与星共存》（Living with a Star）机遇任务，通过测量辐射带电子沉降的时空变化，为辐射带风暴探测器（Radiation Belt Storm Probes, RBSP）任务提供补充观测。此后RBSP任务更名为范艾伦探测器任务。每个BARREL气球均搭载X射线光谱仪与直流磁强计：前者用于测量相对论电子沉降至大气层并与中性粒子碰撞时产生的轫致辐射X射线，后者用于测量超低频（ULF）时标的磁场变化。BARREL的观测站点位于接近南极圈或北极圈的纬度附近，海拔约30公里的平流层高度。在同时获取等离子体波与高能粒子综合原位测量数据的前提下，BARREL仪器实现了首次相对论电子沉降的气球观测，其数据还被用于表征相对论能段电子沉降的空间尺度。

首批BARREL气球科考作业于2013年与2014年的南半球夏季（1月至2月）开展，发射地点位于南极洲的两个科考站：布伦特冰架哈雷湾的英国科考站，以及位于毛德皇后地维斯勒斯卡韦特的南非SANAE IV基地（SANAE为南非国家南极考察队（South African National Antarctic Expedition）的缩写）。2013与2014年的气球科考作业规划构建了由约5个有效载荷组成的观测阵列，覆盖约6个磁地方时（Magnetic Local Time, MLT）时段，该区域经磁映射后对应辐射带区域。由此，BARREL气球星座构成了一个动态且缓慢移动的观测阵列，可用于研究辐射带相对论电子沉降现象。

后续科考作业于2015年与2016年在瑞典基律纳的埃斯兰厄空间中心开展。2015与2016年的作业与范艾伦探测器任务、欧洲非相干散射科学协会（European Incoherent Scatter Scientific Association, EISCAT）非相干散射雷达系统及其他地面与空间仪器协同开展。2015年8月的BARREL作业共发射7个气球，2016年8月的作业共完成8次飞行。

四次BARREL科考作业累计成功发射了超过50个重量约20千克的平流层小型气球。A.J.哈尔福德创建并维护的网站（详见下文信息链接）显示：「截至科考作业结束，已有超过90名研究人员每日与BARREL团队协作，参与7项不同卫星任务、1项其他气球任务以及数量众多的地面仪器相关研究。」尽管BARREL任务在2013至2016年仅开展气球发射作业，但基于这些飞行任务收集的数据的相关研究仍在持续，敬请关注后续进展！所有数据与分析软件均向科学界免费开放。

本资源描述的信息整合自多项BARREL相关资料，主要包括Millan等人2013年发表于《Space Science Reviews》（空间科学评论）的论文、达特茅斯学院BARREL任务官网以及A.J.哈尔福德维护的网站。

当前发布的所有BARREL通用数据格式（Common Data Format, CDF）数据产品均为版本10文件。

BARREL将快速公开所有科学数据产品，但所有用户需阅读并遵守下文列出的《BARREL数据使用政策》。

BARREL数据使用政策

BARREL数据产品向公众免费开放，团队将尽最大努力确保数据产品的最高质量。但仪器或数据处理过程中偶尔可能出现影响数据精度的问题。在可行情况下，高阶数据产品会附带质量标记，已知问题会发布于BARREL数据仓库。若您计划使用BARREL数据进行论文发表或学术汇报，强烈建议遵循以下指南，以确保科研结果的可靠性：
1. 用户应始终使用数据与分析工具的最新版本。浏览用/快速预览图不适用于科研分析或论文发表，未经首席研究员（Principal Investigator, PI）许可，不得将其用于此类用途。
2. 用户应告知BARREL首席研究员数据使用用途与研究目标，以确保数据使用合规，并获取最新版本的数据或分析程序。此外，若BARREL团队成员已开展类似或相关主题的研究，您可寻求其学术协助。
3. 若论文作者列表中未包含BARREL团队成员，用户应按以下方式致谢BARREL团队：本研究使用了BARREL团队（首席研究员：Robyn Millan）的数据，特此致谢。
4. 用户需在提交使用BARREL数据的论文以供发表评审时，向首席研究员提供论文副本。论文发表后，请将引用信息告知首席研究员。

可通过以下邮箱联系BARREL首席研究员：[e-mail]。

《BARREL数据使用政策》文档的在线版本可通过以下链接获取：https://barrel.rmillan.host.dartmouth.edu/documents/data.use.policy.pdf。