A5034936621- Ionosphere and magnetosphere dynamics
- Solar and Space Plasma Dynamics
- GNSS positioning and interference
- Earthquake Detection and Analysis
- Atmospheric Ozone and Climate
- Geomagnetism and Paleomagnetism Studies
- Astro and Planetary Science
- Geophysics and Gravity Measurements
- Seismic Waves and Analysis
- Atmospheric and Environmental Gas Dynamics
- earthquake and tectonic studies
- Minerals Flotation and Separation Techniques
- Geography and Environmental Studies
- Calibration and Measurement Techniques
- Ocean Waves and Remote Sensing
- Precipitation Measurement and Analysis
- Atmospheric chemistry and aerosols
- Atmospheric aerosols and clouds
- Laser-induced spectroscopy and plasma
- Particle accelerators and beam dynamics
- Gyrotron and Vacuum Electronics Research
- Oceanographic and Atmospheric Processes
- Advanced Image Fusion Techniques
- Underwater Vehicles and Communication Systems
- Solar Radiation and Photovoltaics
National Institute for Space Research
2012-2025
Prefeitura Municipal de Campos dos Goytacazes
2003
Universidade do Vale do Paraíba
2001
This work investigates a slightly-deformed cloud of enhanced mesospheric sodium (Na) and potassium (K) layers registered on 24 June 2023 by the dual-beam Na/K LIDAR system operating over low-latitude sector São José dos Campos - Brazil (23.1°S; 45.9°W), region under influence South Atlantic Magnetic Anomaly (SAMA). In this event, these peculiar metal clouds presented strong quick intensification with vertical extension ∼4 km duration only few minutes. At same time, evidence Energetic...
Abstract The paper presents the effects of storm‐time prompt penetration electric fields (PPEF) and traveling atmospheric disturbances (TADs) on total electron content (TEC), foF2 hmF2 in American sector (north south) during geomagnetic storm 23–24 April 2023. data show a poleward shift Equatorial Ionization Anomaly (EIA) crests to 18°N 20°S evening 23 (attributed eastward PPEF) EIA remaining almost same latitudes after PPEF reversed westward. thermospheric neutral wind velocity, foF2, hmF2,...
We analyze in detail the zonal velocities of large‐scale ionospheric plasma depletions over two conjugate stations inferred from OI 630 nm airglow all‐sky images obtained during Conjugate Point Equatorial Experiment (COPEX) campaign carried out Brazil between October and November 2002. The were Boa Vista (BV) (geogr. 2.8N, 60.7W, dip angle 22.0°N) Campo Grande (CG) 20.5S, 54.7W, 22.32°S). Over Grande, measured also by a system spaced GPS scintillation receivers. at sites seen to agree very...
In this work we report a statistical analysis of the occurrence frequency medium‐scale traveling ionospheric disturbances (MSTIDs) observed over Cachoeira Paulista (22.7°S, 45.0°W, −13.2° mag lat), Brazil. The optical signatures low‐latitude MSTIDs in southern hemisphere OI 630.0 nm emission images can be single dark band structure or alternating dark/light bands aligned northeast‐southwest direction and propagating towards northwest. Because feature these events were also referred as...
[1] In this paper, we report a long-term study of medium-scale traveling ionospheric disturbance (MSTID) occurrence using all-sky images O I 630 nm airglow emission. Our is based on 10.5 year data series in which 5.5 years compound new set. The were obtained by an imager installed at Cachoeira Paulista (22.7°S, 45°W, 15°S magnetic latitude). results show the greatest MSTIDs during solar minimum and minor rate descending ascending activity periods. During maximum, have not detected MSTID...
The main purpose of this investigation is to study the ionospheric F region response induced by intense geomagnetic storm that occurred on 7–8 September 2002. index Dst reached a minimum −181 nT at 0100 UT 8 September. In study, we used observations from chain 12 GPS stations and another 6 digital ionosonde stations. It should be mentioned that, soon after sudden commencement (SC) 1637 7 September, TEC variations midlatitude in both hemispheres showed an positive phase. However, during...
Co-seismic ionospheric disturbances (CIDs) are well-documented phenomena typically following medium to large earthquakes. However, several factors influence the detectability of CIDs, and deep-focus earthquakes (depth > 300 km) have long been considered ineffective in generating significant disturbances. Consequently, regions like Brazil, which known for seismic activity, not reported CIDs associated with such events. On January 20, 2024, a earthquake magnitude 6.6 struck near...
This study utilizes 3 years of observational data from the China-Brazil Joint Laboratory for Space Weather (CBJLSW) dual-beam Na-K LIDAR to investigate fast-type sporadic sodium (Na) and potassium (K) layers. The focus is on sudden enhancement these metal densities within thin layers, duration which less than 1 hour. These transient layers were identified in five nights always located a few hundred meters above main Na K There was good correspondence between Ns layer occurrence Sporadic-E...
Abstract. The equatorial ionospheric irregularities have been observed in the past few years by different techniques (e.g. ground-based radar, digisonde, GPS, optical instruments, situ satellite and rocket instrumentation), its time evolution propagation characteristics can be used to study important aspects of dynamics thermosphere-ionosphere coupling. At present, one most powerful large-scale is all-sky imaging photometer system, which normally measures strong F-region nightglow 630 nm...
This paper presents first observations of plasma blobs (localized density enhancements) associated with large‐scale depletions (plasma bubbles) in the nighttime low‐latitude F‐region during a major geomagnetic disturbance. Ground‐based OI 630 nm all‐sky images obtained at Cachoeira Paulista (22.7°S, 45.0°W), Brazil, Appleton anomaly region, showed presence storm April 6–7, 2000 (ΣKp = 38 −/40+; ∣Dst∣ max 288 nT). The emission were used to map spatial and temporal locations bubbles bottomside...
Using two ground‐based all‐sky imaging systems, measurements of moving dark band structures in the OI 630.0 nm nightglow emission were detected low‐latitude region Brazil. On nights 30–31 August 1995, 18–19 July 1998, and 13–14 1999, observations 630 emission, carried out at Cachoeira Paulista (22.7°S, 45°W, magnetic declination 20°W), Brazil, showed that stretched across entire image propagated from southeast to northwest. The observed are thus most likely formed midlatitude move into field...
The sudden enhancement in the mesospheric neutral metal layers (Ns) has been studied different latitudes for decades. Specifically, at 23°S, Sodium Ns have analyzed since their first observation end of seventies. Several studies reported during events energetic particle precipitation (EPP) and formation auroral-type sporadic E (Es a ) high-latitude stations. Es are also observed Brazilian low-latitude sector EPP due to South American Magnetic Anomaly (SAMA). However, despite extensive on...
Ground‐based optical and radio observations were carried out in the tropical region Brazil, during period from October 1998 to September 2000, on several occasions we detected F‐region plasma blob (localized discrete density enhancement) events. These are first of blobs using combined ground‐based techniques. All‐sky images used map spatial extension temporal location ionosonde photometer measurements measure densities. Interesting cases events observed 07, 1999 March 04, 2000 over Cachoeira...
Using ground‐based measurements we investigate the occurrence of dark band structures in OI 630 nm nightglow emission all‐sky images Brazilian low latitude region during periods from January 1990 to December (high solar activity period‐HSA), May 1995 July 1996 (low period‐LSA) and 1997 1999 (ascending period‐ASA). Unfortunately do not have for descending phase period. The obtained these show thermospheric Dark Band Structures (DBS) latitudes propagating southeast northwest. These patches...
Abstract. All-sky imaging observations of the F-region OI 630nm nightglow emission allow us to visualize large-scale equatorial plasma depletions, generally known as trans-equatorial bubbles. Strong range type spread-F is radio signature these (magnetically) north-south aligned depletions. An extensive database all-sky has been obtained at Cachoeira Paulista (22.7°S, 45.0°W; dip latitude ∼16°S), Brazil, between years 1987 and 2000. analysis revealed that relatively few ionospheric depletions...
Transequatorial F region plasma bubbles are large‐scale ionospheric depleted regions that develop in the bottomside of equatorial due to instability processes. Simultaneous all‐sky imaging observations OI 630.0 nm and 777.4 nightglow emissions were carried out at São José dos Campos (23.21°S, 45.86°W; dip latitude 17.6°S), Brazil, during years 2000 2001, a period high solar activity. In this work we present discuss height‐resolved nocturnal zonal drift velocities obtained from observed these...
Abstract. A new ionospheric sounding station using a Canadian Advanced Digital Ionosonde (CADI) was established for routine measurements by the "Universidade do Vale Paraiba (UNIVAP)" at São José dos Campos (23.2° S, 45.9° W), Brazil, in August 2000. major geomagnetic storm with gradual commencement about 01:00 UT observed on 31 March 2001. In this paper, we present and discuss salient features from carried out S. J. three consecutive days 30 (quiet), (disturbed) 1 April (recovery) During...
Abstract. A realistic fully time-dependent computer model, denominated LION (Low-latitude Ionospheric) that simulates the dynamic behavior of low-latitude ionosphere is presented. The time evolution and spatial distribution ionospheric particle densities velocities are computed by numerically solving time-dependent, coupled, nonlinear system continuity momentum equations for ions O+, O2+, NO+, N2+ N+, taking into account photoionization atmospheric species solar extreme ultraviolet...
Abstract. A two-stage VS-30 Orion rocket was launched from the equatorial launching station in Alcântara, Brazil, on 8 December 2012 soon after sunset (19:00 LT), carrying a Langmuir probe operating alternately swept and constant bias modes. At time of launch, ground equipment operated at stations showed rapid rise base F layer, indicating pre-reversal enhancement region vertical drift creating ionospheric conditions favorable for generation plasma bubbles. Vertical profiles electron density...
Abstract The present work shows for the first time study of morphology mesopause sodium (Na) and potassium (K) layers simultaneously observed by a dual‐beam LIDAR in Southern Hemisphere. We analyze these two alkali metal from November 2016 to February 2019 measured at São José dos Campos (23.1°S, 45.9°W) their nocturnal seasonal behavior. night 25 April 2017 was investigated as representative vertical descending structure frequently density data this location. discuss here chemical dynamical...