## 5 Conclusions  
In arc volcanism, constraining the composition of noble gases is difficult, as they are prone to modifications starting in the wedge, due to the possible influence of subducting slabs, and potentially continuing in the overlying continental crust. Here, we reported the first data of noble gases (He, Ne, Ar) for FI trapped in Ol and Px crystals from the Telica and Baru volcanoes, located in the Nicaraguan and Panamanian segments of CAVA, respectively. Previous studies reporting \({}^{3}\)He/\({}^{4}\)He data for these volcanoes were limited to measurements in spring gases, which are known to be potentially prone to the addition of crustal He. The most important conclusions of the present study are:  
* The magmatic air corrected \({}^{3}\)He/\({}^{4}\)He signature for Telica and Baru is 7.5 Ra and 8.0 Ra, respectively, both within the MORB range (8 \(\pm\) 1 Ra). * A data quality check for our, and previous, \({}^{3}\)He/\({}^{4}\)He measurements in FI, fumaroles and springs from the Nicaraguan and Panamanian arc segments, as well as for other CAVA volcanoes, brought to light an along-arc variability of the Rc/Ra signature. The lowest ratios are found in the Nicaraguan volcanoes, whereas \({}^{3}\)He/\({}^{4}\)He ranges between 7.2 and 7.6 Ra with about 34-35 km of crust thickness. The Pacaya (Guatemala) and Turrialba (Costa Rica) volcanoes show the highest ratios with values up to 9.0 and 8.3 Ra, respectively, being both volcanoes built over about 45 km thick continental crust. * The observed \({}^{3}\)He/\({}^{4}\)He variability does not depend on the variable crust thickness reported for CAVA. Instead, it more likely reflects a contamination of the wedge by slab sediment fluids, which is marked in the Nicaraguan arc segment. The \({}^{3}\)He/\({}^{4}\)He signature of southern Costa Rica and the Baru volcano in western Panama seem to be influenced by change in subduction conditions, the possible presence of a slab window and the contemporary subduction of the Galapagos OIB-like hot-spot track. **Supplementary Materials:** The following are available online at [[https://www.mdpi.com/article/10.3390/app12094241/s1](https://www.mdpi.com/article/10.3390/app12094241/s1)]([https://www.mdpi.com/article/10.3390/app12094241/s1](https://www.mdpi.com/article/10.3390/app12094241/s1)), Figure S1: Mineral Chemistry--Diagram, Figure S2: Plots of Geomarker ratios vs. distance (km) along the arc from the border between NW and SE CAVA, Figure S2: Binary plots of Geomarker ratios, Figure S3: The trace and rare earth element data ratios are plotted in binary diagrams. Table S1: Bulk rock data composition, Table S2: Mineral chemistry, Table S3: Isotopic noble gas data from gases in CAVA literature, Table S4: Isotopic noble gas data from Fls in CAVA literature. **Author Contributions:** Conceptualization, A.L.R., P.R. and A.D.P. ; methodology, A.L.R. and P.R. ; data curation, A.L.R. and P.R. ; writing--original draft preparation, A.L.R. and P.R. ; writing--review and editing, A.L.R., P.R., A.A. and A.D.P. ; funding acquisition, A.L.R., P.R. and A.A. All authors have read and agreed to the published version of the manuscript. **Funding:** This research was funded by the Italian Ministry of Education, Universities and Research (MIUR), grant number PRIN-2017 LMNLAW and \"The APC was funded by A.L.R. waiver by MDPI\". This research was funded by (ANID) Fondecyt Iniciacion a la Investigacion de Philippe Robidoux, Etapa 2021, grant number N11190846. Field and sampling cost during 2015-2016 were covered by Universita degli studi di Palermo (Italy)/Istituto Nazionale Previdenza Sociale INPS/Doctoral research scholarship for international students, and also by Fonds Quebecois de Recherche Nature et technologies (FQRNT): Doctoral research scholarship (B2), 2013-2016. **Data Availability Statement:** The Rutgers University Central American geochemical dataset \"RU_CAGechem\" (DOI: 10.1002/gdij3.10) is consulted and represent database from the Geochemical Database by [PERSON] et al.